Note: All the links are to Allromance, since I discovered them while browsing Allromance
The three first novels in Tessa Dare's Spindle Cove series are discounted to 0.99. While I didn't like the last one (my science background made it had to believe the reason for Miranda's journey), the series is definitely worth to spend 3 dollar on :).
Avon have also discounted several of Jennifer Ryan's novels. I have one of them in the TBR pile, so I am not buying another book by her until I have read that one.
Crazy by You by Rachel Gibson is discounted to 1.99, and several of her other novels are 3.99.
Several of Johanna Lindsey's backlist are discounted to 1.99, and the rest are 3.99. Which is a pretty good price.