It is sometimes difficult to get rooms in the area during the weekend. The past two years I have stayed in places north of the Glen. I can't recall the names, but last year's stay was in a winery that was quite nice, but also pricey, and about 20 miles north. However, I went with my son, and it was a special weekend. I have not booked for this year yet, as I was not sure about firm plans, so I will be in the same boat as you, trying to find a room.
There is always a great turnout of vintage cars - both racing and show. They have a good show of older sports cars in the infield, and walking through the pits is like Christmas morning (I used to get car model kits for Christmas). The variety of track cars is fantastic, from little Fiats with windup keys on the back, to 500 h.p. beasts. There are always some nice 356's.
Bring a folding chair, a hat or an umbrella, and lots of stuff to drink (water, that is). It's a great weekend, and if you can make the Friday, they always have a special event in town that recreates the older days at the Glen. You can drive the original track route that went out of town and then back through the village (they used regular roads back then for the race)
You'll find the full program on the Glen website.
Bob