Say "I Love You", one of the best romance anime I've seen.
Kimi ni Todoke - From me to you, This is also good, gets some nice romance and drama.
Kimi no Iru Machi, A place where you lived, Very good drama, quite a popular manga right now.
Ef - Tales of Memories and Ef - Tales of Melodies are both realy good, especially tales of memories. Might be a bit confusing at first, but gets really good.

True Tears and White Album, I have yet to see these, but heard they are pretty good, white album just recently got a second season.