MY DARLING FINGER is worn to a nub, but I have learned something that's useful for anybody hoping to spend the holidays at a nearby resort.

Perhaps you didn't get around to thinking about a Christmas getaway until recently, and the top resorts are telling you they're booked solid. Yes, you should have called earlier -- but don't give up too soon. Six weeks before Yorktown's recent celebration, there wasn't a room to be had in the Williamsburg Inn. Yet on the Friday of the actual weekend, several people walked in without reservations and were shown to rooms available because of cancellations.

People's plans change; they get sick or relatives die or they have second thoughts about getting on slippery or traffic-choked roads. If you don't mind hanging loose, you may profit. The rest of the good news is that -- if room roulette is not your style -- there are still, at this writing, rooms at top places. (Could be the recession, though no one is admitting it.)

The Williamsburg Inn is again booked solid for the Christmas season. But Randall Foskey, press bureau director for the restoration, says that if your heart is set on the Inn, the management will put you on a waiting list for some of the inevitable cancellations. "It always happens," says Foskey. And, of course, few places put on a Christmas like this handsome hostelry. Daily rate for a double, without meals, is $76-$105.

But as we said, some of us don't really like not knowing until the last moment where we will lay our heads, and fortunately there's another answer if you want to spend the holidays in Williamsburg.

Call Innkeepers of Williamsburg, an organization which represents 50 innkeepers and offers accommodations ranging from modest to fairly stiffly priced. One call will tell you what's available over the holidays (at last report there were plenty of rooms). From the District or Maryland, the toll-free number is 800-446-9244; from Virginia, 800-582-8977.

Some, like the Holiday Inn 1776, have their own ceremonies such as the Christmas Eve yule log; some, like Fort Magruder on York Street, are only a convenient block or so away from the restoration where Christmas is being given proper respect for how it once was. Some have their own restaurants and all offer an award-winning magazine beside your bed to clue you in on where to go and what to do.

There's plenty to do, as usual, from the Grand Illumination on Dec. 16 to checking out this year's decorations on the spectacular cedar Christmas tree at the Abby Aldrich Rockefeller Folk Art Center. On Dec. 15, Bruton Parish Church will ring to Handel's "Messiah." New Year's Day 1982 will get a special salute on Market Square Green.

The restaurants are easier to get into at this time of year than they were during the summer (Colonial Williamsburg is open all winter), and just to walk down Duke of Gloucester Street where the Christmas greens adorn nearly every door is to step back into a simpler world with old-fashioned values. And don't forget that no reservations are needed at the Inn for lunch or breakfast; those two meals are a less expensive way to sample the food. The Birchermuesli (a Swiss breakfast dish based on cold oatmeal, fruit and cream) is said to be a must.

The reservation line for the Greenbrier in White Sulphur Springs, W.Va., is as busy as Amtrak's, but there were still rooms available when I checked. Call 800-624-6070 for a three-night minimum stay between Dec. 22 and New Year's, and you'll get not only breakfast and dinner included in your approximately $80-per-person-per-night price, double occupancy, but a Christmas package of things to do every minute.

The Greenbrier raises their normal rates a bit for the season, but you'll hardly notice the pain with all the goings on -- musical programs, financial and literary seminars to improve your mind, cooking demonstrations and wine tastings and, on Christmas Eve, an opportunity to watch the hotel's culinary staff carve a life-size Santa and his sleigh from a block of ice on the lawn. A flesh-and-blood Santa will arrive by sleigh or cart, according to the whims of the weather, and children will have their own program. (If you're coming alone and would like to make friends, ask to dine at the Holly Table.)

The Homestead in Hot Springs, Va., closest of all the big resorts to Washington and wearer of a five-star award from Mobil Guide like its competitor the Greenbrier, is booked solid for the holidays. But John Gazzola, public relations director, goes right out on the limb anyway and says, "Get on the waiting list and there's a reasonable chance of getting in."

About 100 names are already on the list, but since the venerable old hotel can accommodate 1,100 guests, tucking in a few more is often possible. From December through Jan. 2, the daily rate is $79 per person under the full American plan, double occupancy. The Homestead, of course, has skiing and a well-known spa where you can get yourself limbered up again after a fall on the slopes. Call 800-336-5771.

Up in Pennsylvania, the Hotel Hershey, grande dame of the chocolate capital, reported it still had room. They also are laying out quite a Christmas celebration -- carols, chestnut roasts, dancing, and a Festival of Food and Light to kick off the big week on the 20th. And they're planning special dinners with madrigal entertainment from the 21st through the 23rd. Santa will be making a stop here as well, bringing gifts to the children. The whole package costs $58 a day per person under the modified American plan (two meals). If you stay two days or longer midweek, you get $5 off. Call 717-533-2171.

You can't get into the Tides Inn, in Irvington, Va., for Christmas, but the management would be happy to have you for a minimum three days on the New Year's weekend. There's boating every day in this water-oriented resort and a gala ball planned for Dec. 31. Daily tariff is $58-$73 per person double occupancy, full American plan. Call 800-446-9981.

And lastly, there's a sleeper up in Lancaster County, Pa., which I have not seen but which is by all reports putting on quite a Christmas. The Historic Strasburg Inn, part of which was once an old tavern, is planning a sort of Williamsburg-type program with a local Pennsylvania slant. There will be something doing every night for the traditional 12 days of Christmas, beginning with the Fire of Joy, a roaring bonfire accompanied by the firing of guns on nearby farms to herald Christmas.

The inn is located on Rte. 896 in eastern Lancaster County, and more information can be had by calling 717-687-7691. It is a 2 1/2-hour drive from Washington.Of course, by the time this is published, you may discover there's no room at the inn of your choice. So if you celebrate Christmas-New Year's at home, you may decide that the best way to recover from the holidays is to make an early January reservation soon after your last guest leaves.