THE BOOK-COLLECTING visitor to London should aim to acquire two books right off: The Bookshops of London by Martha Redding Pease and Driff's Guide to All the Second-Hand and Antiquarian Bookshops in Britain. The two are as different as Farringdon Road and Heywood Hill, but both are essential. Pease covers new, used and antiquarian shops, offers addresses, telephone numbers, nearby Underground stations, and each store's special expertise. Driff's focus is both wider and narrower, but what makes his guide special is the commentary: Driffield -- no one knows his first name and he goes simply as Driff -- mocks, libels, and blasts his subjects with an undisguised glee, verging on scurrility. He is the John Simon or Joan Rivers of second-hand book runners. Hatchards "always looks like a country house where they have been selling off the library & put the bks sideways so that nobody will notice." Of B. Stone's, "I'm always keen on children's bksps, there is never any fear of children being allowed in the places." Driff also publishes a biweekly magazine, called simply Driff's, equally vituperative and useful (three issues offered poet-dealer Ian Sinclair's comprehensive catalogue of the beats), but somewhat hard to come by. It is carried by Compendium (234 Camden High St. NW1, 485-8944), though, the best of London's leftish-feminist-alternative bookstores. SOME COLLECTORS, forced by well-meaning spouses or friends into museums, theaters and churches, may only have a limited time for their booking. Here, briefly annotated, are some of the notable biblio hot spots of London and Oxford. LONDON

Skoob (15 Sicilian Ave. Southampton Row WC1; 404-3063): My favorite second-hand shop in London. A family business (you may find the Ongs at lunch or tea), with a good range of books on all topics. I picked up a signed Chesterton for 6. Some literary magazines. Reminiscent of D.C.'s Second Story Books. Bertram Rota (30 Long Acre WC2, 831-0723); Bernard Quaritch (5 Lower John St. W1, 734-2983); Pickering and Chatto (17 Pall Mall SW1, 930-2515): Less book shops than book sanctuaries, anyone without a title is likely to feel intimidated here. Still, these are places book lovers should go, if only to glimpse the rarities. Fantasy Centre (157 Holloway Road N1; 607-9433): Looks like a thrift shop, but is probably the best out-of-print store in London for fantasy and science fiction. Here I purchased the now scarce first volume of John Sladek's Roderick books. For new science fiction, check out Forbidden Planet (23 Denmark St. WC2, 836-4179) -- though their New York shop is bigger and more extensive. Any Amount of Books (103-105 Hammersmith Rd. W6, 603-9232): I can't help but think that grammar calls for Any Number of Books. This is perhaps the best of the Charing Cross second-hand shops, though I don't think much of any. The others, just down the street, are Henry Pordes, Reads and several in Cecil Court -- overpriced, touristy, dull stock. Still, if you're in the area, check them out. I bought a pretty copy -- 4 -- of Charles Williams' (he of Inklings fame) A Brief Life of Shakespeare: based on the Edmund Chambers two-volume classic, it presents all the facts in a crisp, compact form. Dillons (Gower St. WC1, 636-1577): This is the bookshop of the University of London, and worth a quick glance from anyone visiting the Courtauld. It has a marvelous brick baroque exterior. The new section is excellent, but the second-hand books are few and overpriced. The Flask Bookshop (6 Flask Walk NW3, 435-2693): Located in Hampstead, this shop is pleasantly crowded, and bargains are possible. John Clute picked up Peter Dickinson's The Weathermonger, his first book, for 50 pence; I found Many Inventions for a couple of pounds. This shop certainly offers a very pleasant change from all that fresh air, trees and wind out on the Heath. Foyle's (119 Charing Cross Rd. WC1, 437-5660): Supposedly the biggest bookstore in the world and absolutely infuriating. No one knows anything; it's impossible to find the books you want; and the place is cavernous. Don't bother. For new books, try Waterstone's next door. The Cottage Book Shop in Penn (Elm Road, Penn, 2632): If by chance you are motoring in the environs of London, check out this shop. Extremely cheap, the stock is enormously varied, and the shelves crammed with much that no one would ever want. Perfect for anyone thirsting for the essays of E.V. Lucas or Augustus Hare. Still, I picked up Kipling firsts for a pound a book, a charming little volume of Gunning's reminiscences of Cambridge for 40 pence, and the extremely hard-to-find novel by Daniel Vare, The Maker of Heavenly Trousers (another Perrin "Rediscovery"). The slightly pricier Weatherheads (58 Kingsbury, Aylesbury, 23153), in nearby Aylesbury, is also worth a visit. I picked up three of the classic Temple Dante translations there. OXFORD The best is Robin Waterfield (36 Park End St., O865-721809): near the train station. Lower floors are antiquarian. Top floor has extensive holdings in forgotten fiction, but bargains can be found. Lots of those blue Oxford classics, back issues of Horizon, off-prints from scholarly journals. Picked up two novels of Thomas Love Peacock, F. Anstey's collected fantasies, and an odd book of conversations: Talking of Dick Whittington by Hesketh Pearson and Hugh Kingsmill, both popular litterateurs of the '40s whom I collect for slightly unfathomable reasons even to myself. (Both men write very well, though.) In three or four visits over as many years Waterfield's has never had any plastic bags for purchases. Fortunately, I had stopped earlier at the Bodleian Library, which anyone in Oxford should visit, and bought -- as a gift -- one of the handsome Bodleian book bags. Blackwell's (48-51 Broad St., 0865- 249111): Most of this Oxford classic's rare stuff is out at Fyfield Manor, which I didn't visit, partly because the second-hand books in town, though desirable to anyone of a scholarly bent, were somewhat dear. I was tempted by the Harold Williams' edition of Swift's Tale of a Tub -- a favorite author in the standard text -- but 15 seemed rather high. Instead I picked up a little paperback pamphlet of Gibbon's Vindication for a pound. Also be sure to seize on the free guide to the second-hand shops of Oxford. Anyone looking for European books should check out Blackwell's very good foreign language section. Thornton's (11 Broad St., 0865-242939): Although this shop enjoys a good reputation as a scholarly second-hand resource, I found the shop assistants less unhelpful than ignorant, and most of the books out of reach: you need a ladder to get to the upper shelves and the ladder was impossible to move around easily. One also feels a bit like an intruder here; on the history floor the clerks were clearly more interested in their own correspondence than in helping an American find the letters of Edward Gibbon. Swift's Turl Cash Bookshop (3 The Turl, 0865-240241): This proved a real find. The place looks stuffy and forbidding, but the manager was pleasant, didn't bother me, and there were a good half-dozen books I was happy to acquire: Julian Symons' biography of his brother A.J. Symons (known for The Quest for Corvo), Johnson's England (a two volume set of essays on the 18th century), an English first of Italo Svevo's As a Man Grows Older, a pocket edition of Clarendon's history. The prices were fair, but the store takes cash only, so make sure you've stopped at the bank. THERE ARE, of course, dozens of worthy book shops scattered throughout London. One sunny afternoon I sauntered down Islington's High Street -- a very working-class neighborhood -- and found three second-hand shops, all of them rather impromptu affairs, but in one of which I discovered Paul Ableman's I Hear Voices for 20 pence. Nearly all the street markets -- Camden Passage, Camden Lock, Lower Marsh and the Cut -- will offer old books, sometimes of quite good quality. Even Harrod's sells second-hand books -- the older titles from its lending library. In Oxford I also wandered into a dealer's nook in the covered market, where I pounced on a first edition -- second state, alas -- of C.S. Lewis's Out of the Silent Planet, a book worth at least 20 times its asking price of a pound. Besides the Royal Pavilion, Brighton also hosts several good book shops, including three on Duke Street in the center of the tarted up, but still charming, area called the Lanes. (In one I found all three hard-to-come-by volumes of Robert Musil's The Man Without Qualities.) On the Welsh border, Hay-on-Wye advertises itself as an entire village of bookstores, but I have yet to get up there: perhaps next time. Who knows what treasures await? For now, I have the problem of finding room in an overcrowded house for the books I already have.