Sears knew it before he teamed up with Roebuck: Americans can spend a fortune without leaving home.

So clear the aisles and buy by the books. Herewith, a concatenation of catalogues.

Frontrunner for decadence is the NEIMAN-MARCUS catalogue (800/527-5800). This year, its pages hawk the "LaserTour" by Perceptronics for the fitness buff on your list. It's an exercycle plugged into a video-disc system, with views of beach bikeways, Beverly Hills streets and Southern California canyons complete with increased pedal tension on uphill climbs. A mere $20,000 delivered. But then, everyone will have thumbed through Neiman's order form. To avoid duplication under the tree, you may want to check the season's more arcane publications. THE COCKPIT -- outfitters for the National Air & Space Museum -- offers authentic WWII, pre-war and current-issue clothing on the aviation theme (212/420-1600). Flak helmets. Burma tropical flight boots. Forty- year-old sheepskin flight jackets. And an aerial depth bomb converted into a wood stove for $395. (Remember, the catalogue warns, "All items are sold in 'as is' condition.") Hefty novelties from L.H. SELMAN LTD. start to look alike by page five. They're antique and new paperweights, ranging from a few hundred to a few thousand dollars apiece. The Antique St. Louis, in which "a colorful arrangement of turnips forms a refreshing still life displayed on a white latticino cushion," goes for $750 (800/538-0766). Consider the Mini Flare Gun from PAPILLON (800/228-1244): A practical gift, "the tiny take-along that could save a life" signals for both alpine and sea emergencies with 10 flares in assorted colors. It comes with 32 charges and instructions, for $46.

VICTORIA'S SECRET, designer lingerie from San Francisco, promises a different sort of fireworks. According to the catalogue, "this is the season of romance." Also of bikinis, G-strings, garters, merry widows and miscellany in satin. (800/323-1717, operator 311). ALLURING DESIRES of Fort Lauderdale airbrushes its collection of camisoles, baby dolls et al, and slips in a $4 coupon toward something comfortable (800/327-3729). Button-down types can cut loose with BAKER STREET SHIRTMAKERS' Oxford stripes. Nothing more adventurous here than a workshirt (800/528-6050). Likewise VICTORY SHIRTMAKERS in New York deals in corporate broadcloths; this year they've returned to sending swatches with their catalogues (212/687-6375). LAURA ASHLEYoutfits the prim set by mail in "the simple lines and sturdy good looks that our ancestors first wore." Lots of gathered sleeves and puffed shoulders, Edwardian, Victorian and other ancestral types; most of the dresses seem to have matching print curtains and bedspreads (800/526-6383). Interfacing on the shuttle? Execs on the go naturally need "The Link," Panasonic's thousand-dollar computer in a briefcase, complete with printer, telephone hook-up and expansion capability (the video screen isn't included.) MACY'S delivers, add $7 (800/528-6602) Soup-to-nuts department: THE POPCORN FACTORY mails cheese-flavored, caramel and buttered kernels in painted 61/2-gallon tins for $24.95 (800/621-5559). CAPTAIN COOKIE, all-natural chocolate-chip cookies ranging from 16 inches to 21/2 feet in diameter, are $29 plus shipping from New York. The Preppie Alligator cookie comes trimmed with pink and green icing (800/431-2332). A 16-ounce milk-chocolate Mercedes-Benz ($16) from the 1982 CHOCOLATE CATALOG melts in your driveway (800/325-8881). GARFINKEL'S dishes "almost sinful" truffles by Candy Jar of San Francisco (459-9633, ext. 777). A lifesize female torso in milk or dark chocolate from KRON CHOCOLATIER is likewise unavailable in vending machines (966-4946). There's always the WISCONSIN CHEESEMAN'S spreads, logs, wedges, paks and sidelines of jams, cakes and candy. The "dietetic pak" includes "two types of 99.9% cholesterol- free dietetic substitute process cheese." Tempting (608/837-4100). And more of the same, sweets-, cheese-and sausagewise, from FIGI'S of Marshfield, Wisconsin, plus enough dried fruit to feed a small country (800/468- 1562). That annual aberration, DeLuxe fruitcake, "custom baked only by the COLLIN STREET BAKERY in Corsicana, Texas," is $9.15 for a two- pounder; cut rate after your first 24 cakes (800/255-9206). A suckling pig is a surefire conversation piece at $89.95. PFAELZER BROTHERS of Chicago will ship it and all manner of primo surf and turf, raw or otherwise, per your toll-free order (800/621-0226). Smoked salmon flown weekly from Scotland is available from MACY'S, $78 for three pounds. And pistachios, roasted to ZABAR'S specifications, are shippable in five-pound bags from the New York deli for $27.95 (800/2221-3347). Kitchen snobs no doubt already own asparagus- and potato-peelers (the latter electrically strips down six to eight taters in two minutes), $4.50 and $27, respectively, from THE CHEF'S CATALOGUE (800/331-1750). But how about Eggrite? The high-tech egg timer changes color to indicate the exact doneness of boiling eggs, taking altitude and amount of water into account, $6.50 from WILLIAMS-SONOMA (415/652-9007). Or a diver's helmet ice bucket from HOFFRITZ? Holds three quarts plus everyone's sloshed attention (466-4382). Who else would describe a fire-engine-red Royal Stewart tartan tie as "colorful, conservative and correct"? THE SCOTTISH LION in North Conway, New Hampshire, sports kilts, tartan scarves and plaid blankets, Balmoral and Glengarry bonnets, sporrans (those tassled purses of black pig-grain hide), a pipe, drum and bagpipe record album and closets full of clan clothes (800/258-0370). On the other hand, HAMAKOR JUDAICA of Chicago, "the source for everything Jewish," sells satin yarmulkes by the dozen in a dozen colors (including peach, lavender and burgundy), all manner of menorahs, prayer shawls and other holiday gear from Israel (800/426-2567). "Dear Art Enthusiast," reads the mailer accompanying the ORIGINAL PRINT COLLECTORS GROUP catalogue from New York. The booklet touts the economic benefits beyond any aesthetic reasons for art-shopping. The brochure of limited-edition prints spares buyers from ever venturing into a gallery (212/685- 9400). Attention, shoppers: ALTMAN'S CHRISTMAS BOOK pitches an $80 decanter in the shape of a 1937 Packard that can hold 16 ounces of booze (800/228-5444). BERGDORF GOODMAN is pushing camel-suede ponchos trimmed with Canadian sable tails for $2,950. One size fits all. Bergdorf's also puts an end to disorderly fruit bowl scenes with dainty grape shears/nutcracker combos in silver for $95 (800/247-2477). Jade fondling stones may be the mood rings of '82. GUMP'S of San Francisco says the polished pieces have spelled relief in the Orient since Confucius' day. They come in leather carrying pouches for $25 (800/227-4512). And I. MAGNIN'S silver- plated tape measure in the shape of a walnut, no less, is both standard and metric for $12 (800/227-1125). Your name here . . . SAKS FIFTH AVENUE'S "monogram boutique" will initial anything -- including a "carry-along Sweet'N Low case that holds four packets" for $20. Casual and lots of fun (800/221-3505). WALTER DRAKE of Colorado Springs offers a golf ball personalizer to end confusion on the fairway (303/596-3854). And to make spending special, FORTUNOFF JEWELERS pitch a silver-plated credit card holder for $11.99, with three letters engraved, free (800/223-2326). Vermont's ORVIS offers a field day of duck head shower hooks, decoy curtains, mallard bookends, quail thermometers, pewter waterfowl mi stock a pond to serve as a potential protein supply for a rural village." (800/228-1666). More cards, letterheads and calendars from THE DRAWING BOARD in Dallas come with a bonus acrylic tree ornament (800/527-9530). "Over 2,500 great gift ideas" are promised by PUBLISHERS' CENTRAL BUREAU'S catalogue. "Chuck and Di Have A Baby" paper doll book, "The Beverly Hills Diet" and Stephen King's latest, "Firestarter," are among the titles getting holiday plugs. (Dept. 182, 1 Champion Avenue, Avenel, N.J. 07131). NATIONAL GEOGRAPHIC'S biggest draws are mural maps of the world, $48 for a reproduction of a 17th-century chart on simulated parchment, $58 for an up-to-date version (948-8971). Other local entries include THE GAME ROOM'S "Bozonomics" dart game for $7.95. Score 240 points, win a presidential R.I.F. (722-0040). THE FOLGER'S T-shirts, (including that local favorite, "The first thing we do, let's kill all the lawyers" -- from "Henry VI, Part II"), are $9.95 plus $1.05 shipping (546- 2626). And the SMITHSONIAN catalogue features a Bug House for "prize catches" plus illuminated magnifier, $8.50 (455-1700). Washington's W. CURTIS DRAPER TOBACCONIST (638-2555) offers a pageant of pipes, cigars and fancy cigarettes complete with the Surgeon General's warning. There's a lighter in the shape of a hand grenade, a guillotine chrome cigar cutter and a humidor moistener bottle. Plus! "For an investment of $25,000 and a six-to eight-month wait, you can join a small group of reasonable men, not all of them wealthy, but each the owner of a matching set of Ben Wade Danish Hand Model pipes." It's a toss-up from STEUBEN. Will it be the crystal ball for $795 or 14-karat gold cufflinks for $750? Perhaps the "Frog Prince," a six-inch glass figurine with an 18-karat gold crown, out of the Grimm brothers' budget at $2,450 (800/223-1234). As always, L.L. BEAN (207/865-3111) offers welcome utilitarian alternatives from Freeport, Maine. Their functional buckskin mittens, woodsman's heavyweight water-repellent pants and "Trooper Style" cold-proof hats come fully assembled, batteries not included. CAPTION: Picture 1, For only $20,000 you can tour Southern California sans smog, via the Laser Tour exercise bike from Neiman-Marcus. A great way for flabby rich folks to tone up while avoiding muggers, kidnapers and Democrates.; Picture 2, This silver-plated measuring tape's just the thing for your nutty Aunt Martha's sewing kit.