Great site with a complete 一覧 of 人気 asian drama/movies. Updated many times a day! Coffee Prince, Hana Kimi, Why Why Love, Romantic Princess, 9 End 2 Outs, Meteor Garden, Liar Game, and many many more!!!
Very helpful site that has an extensive index of Korean (as well as Japanese and Taiwanese) dramas along with links, when available, to YouTube 動画 of the dramas.
eHit doesn't specialize in Korean dramas, but it has a decent selection. Only downside is that the rental plan uses a (sometimes) confusing points system (rather than a standard monthly rate).