There is a lot of good historical romance deals, right now. 

I love Patricia Rice’s novels, and right now she is offering a sale on two of her books. 
Denim and Lace  and The Genuine Article is discounted to 2.99. If you haven’t tried Patricia Rice yet, this is a great time.  

There are also a bunch of Johanna Lindsey titles available for 3.99 or less at Allromance right now.

And there are also some Dabwaha deals:

The Governess Affair by Courtney Milan is free right now. 

A Lady by midnight by Tessa Dare is discounted to 2.99 right now.