Well Truce at Bakura is the book that comes directly after the last movie (episode 6) so that is a good place to continue.
The first actual Star Wars books were written by Timothy Zahn and the trilogy is called "The Thrawn Trilogy" The author is actually the one who came up with name Coruscant. It is still one of the best star wars series EVER!! But there are about 350 SW novels (referred to as TEU, ie the expanded universe) so it all depends on what you like... You into the Old Republic era? There are books set thousands of years before the movies, there are stand alone books set directly before and after each movie as well.
The Rise of Vadar series is also awesome, along with the Death Star book
(I could go on and on, lol)
List of Star Wars books - Wikipedia, the free encyclopedia