Don't have a reccomendation for you, but the first book store that I ever saw a "gay interest" section was a Super Crown in La Jolla CA. It was probably back in the mid 90's when I first found it, and it was a pretty well stocked section. Once while browsing in it I kept noticing a beady eyed short man trying to act like he was going to accidently go down the aisle there, but he seemed to keep losing his nerve. He made about four or five attempts before giving up.
EDIT TO ADD: Actually, I do have a reccomendation for you. I have a photo book called Gay Pride by Fred McDarrah. It's a chronological LGBT history book, it even has photos from the night of the Stonewall riots.