Middlesex is the first one I thought of.
Rita Mae Brown, who also writes mysteries, has written some lesbian fiction. Rubyfruit Jungle is one title, I think.

Armistead Maupin's Tales of the City series and virtually all of his books deal with homosexuality. Very entertaining, too.

Sarah Waters writes excellent, excellent historical fiction where the main characters are gay. Be warned, if explicit sex scenes bother you, you'll want to avoid Tipping the Velvet. The rest of hers are quite tame though (IMO).

Edmund White's autobiography, A Boy's Own Story.

Maurice, by E.M. Forester. A shorter work, published posthumously in the 70's if memory serves. The main character is Lucy Honeychurch's (A Room With A View) brother.

Interesting thread. Does anyone know of any classic books where the themes center on homosexuality? I know of only a couple.

I read Oscar Wilde's 'The Picture of Dorian Gray' a few weeks ago. I did not really enjoy the book itself (I am SO against the ideas of aestheticism), but the endnotes were interesting. It was facinating to see what Wilde's editor cut out of the original because of the hints of homosexual activity.

I have yet to read 'Brideshead Revisited', by Evelyn Waugh. Another on my list is 'Madamoiselle de Maupin', by Theophile Gautier. From what I understand, there is some homosexuality and cross-dressing in it.
CMK

The Well of Loneliness by Radclyff (sp?) Hall is about an Englishwoman who is a Lesbian.

Any of the biographical works of the late May Sarton.

Wow awesome tips everyone!
Keep em coming!

I read all of Nevada Barr's Anna Pigeon series, but discovered another side of her, in Bittersweet

They might be pretty dated, but James Baldwin wrote several semi-autobiographical novels including: "Giovanni's Room (1956), about a white American expatriate who must come to terms with his homosexuality, and Another Country (1962), about racial and gay sexual tensions among New York intellectuals.

"Portrait of a Marriage" by Nigel Nicholson is about his mother, Vita Sackville West and her affairs.

Hmm, well I found this to be an interesting read: http://www.amazon.com/Stranger-Gate-Christian-America-Plume/dp/0452273811/ref=pd_sim_b_4
And yes Prayers for Bobby is an incredible read. Much more profound because it is a true story.

I second Armistead Maupin's delightful Tales of the City series, which so captures an earlier era in San Francisco.

The same with May Sarton, especially "May Sarton", by Margot Peters, a riveting biography. Be warned, though, May was not a nice person.

Then there is And The Band Played On, by Randy Shilts, a masterly study of the onset of the AIDS epidemic. I have read and reread this book, which is alternately horrifying, tragic and infuriating. It just about killed me when he died (of AIDS); to read his work is to love him. The TV movie made from the book is a travesty.

There is also The Mayor of Castro Street, also by Randy Shilts, about Harvey Milk

There are probably some good reading lists on the net. The ALA (American Library Association) might have some recommendations. The older titles, though "classics", are problematic. It was pretty much impossible for a book about a gay man or a lesbian to be published unless they died at the end of the book. I would suggest searching out contemporary titles, which will likely present more authentic portrayals.

Oranges Are Not the Only Fruit by Jeanette Winterson is about growing up lesbian in a strict Christian community.

I just found out that there's going to be a Prayers for Bobby movie this weekend on Lifetime... I've seen a bunch of commercials all week! You can check it out here: http://www.youtube.com/watch?v=4vAfBXW1e6U

Here is a link that might be useful: Prayers for Bobby Trailer

Alan Hollinghurst's books have strong homosexual themes. He's been shortlisted for the Booker Prize for his book The Folding Star and actually won the Booker in 2004 with The Line of Beauty.

Might I suggest Florence King's Confessions of a Failed Southern Lady? A humorous memoir that isn't about becoming a lesbian, but doesn't ignore that aspect of her life.

I second any Florence King book --- every one is insightful and entertaining.