If you like romances you might want to pick up the 16 free titles that Harlequin is offering. (Heck, even if you don't enjoy romances, you might want to pick these up because they're free. Maybe you'll lend your Kindle to a friend who really likes romance novels.)
You can get these directly from Harlequin at
http://www.harlequincelebrates.com/ or from Amazon. If you get the books from the Harlequin site, you'll have to convert from MS Reader (.lit) or ePub format to the Mobipocket format which the Kindle reads.
Here's the list of the titles and links to their pages at Amazon. (Categories provided by Harlequin at their site.)
Suspense and Paranormal
Crime Scene at Cardwell Ranch by B.J. Daniels
Hide in Plain Sight by Marta Perry
Stranded with a Spy by Merline Lovelace
Kiss Me Deadly by Michele Hauf
Passion
Slow Hands by Leslie Kelly
Price of Passion by Susan Napier
Baby Bonanza by Maureen Child
Irrestible Forces by Brenda Johnson
Home and Family
Once a Cowboy by Linda Warren
Dancing in the Moonlight by RaeAnne Thayne
Snowbound by Janice Kay Johnson
Romance
Speed Dating by Nancy Warren
A Very Special Delivery by Linda Goodnight
The Bride's Baby by Liz Fielding
Historical
His Lady Mistress by Elizabeth Rolls
Homespun Bride by Jillian Hart