I'm surprised there isn't a thread for this yet. I figured I'd start one: A list of yaoi titles that I'd recommend or even some that I've just heard might be good to check out.
Sekaiiachi Hatsukoi – yaoi, romance, love-hate relationship, complicated past. Season two of the anime will be premiering shortly. Sometime in October, I believe.
Sorenari ni Shinken Nandesu – yaoi, cute romance, playboy falls for single parent.
Koisuru Boukun – yaoi, unrequited love, student loves his sempai. Came out with 2 OVAs.
Papa I love you - yaoi, incest, family, age gap. It's not exactly what you are thinking and turns out to be a rather cute story.
Totally Captivated - shounen-ai. What's not to love about this series?
Sakura-Gari - yaoi, mature, rape. A rather tragic story, but one I found worth reading.
Wild Fangs, Wild Rose, and Wild Wind - yaoi, fantasy, supernatural. The second one, Wild Rose, was probably my favorite just because of the love-hate relationship between the main characters.
Acid Town - My favorite series by far! shounen-ai, angst, dark past, yakuza, and unrequited love.
Gokujou no Koibito - yaoi, modeling, glasses, age gap. There was one OVA for this one. I probably liked this one because of Masahiro, the manager, with his long hair and glasses.
Here are a few that I'm currently reading, which I think are good so far:
Super Lovers - shounen-ai/yaoi. It looks like this one will be one of those ones that continually yanks at your heart.
Seven days - Shounen-ai, school life.
Komatta Toki ni wa Hoshi ni Kike! - shounen-ai, slow romance.
Yatteraneeze - yaoi, opposites attract.
Haru wo Daite Ita - yaoi, AV models, love-hate relationship. I love both the main characters in this series! They are drawn to perfection! They also made 2 OVAs for this.
Okay, that's all I can think of....for now :D
Please feel free to add to this list some that you might recommend.