Here's my schpeel...
Reading for Old Republic Based Knowledge (Preparing for SWtOR):
If you're looking to bone up on your knowledge of the Old Republic era and/or the events surrounding the OR era in SW history, whether out of pure interest or in an effort to get ready for SWtOR, read the following:
Revan (scheduled to be released later this year)
Deceived
Red Harvest (a "horror" novel, not recommended by most people, but may interest some)
Fatal Alliance
Darth Bane: Path of Destruction
Darth Bane: Rule of Two (technically takes place during the Rise of the Empire era in SW history, but still relevant)
Darth Bane: Dynasty of Evil (technically takes place during the Rise of the Empire era in SW history, but still relevant)
Reading Chronologically:
If you are looking to start reading chronologically, then make sure to follow wookieepedia's Timeline of Books. I generally stick to the "Adult Novels", but I have heard good things about some of the other types of books (ie Young Adult, etc) from some people.
Reading Only "The Best" SW Novels (Disregarding Reading Chronologically):
If you're looking to just read the cream of the crop, best SW books available and don't mind jumping around time periods, then here are my top recommendations:
The Darth Bane Trilogy (Path of Destruction, Rule of Two, Dynasty of Evil)
Cloak of Deception
Darth Maul: Shadow Hunter
Outbound Flight
Han Solo Trilogy (The Paradise Snare, The Hutt Gambit, Rebel Dawn)
Splinter of the Mind's Eye
Shadows of the Empire
The Bounty Hunter Wars Trilogy (The Mandalorian Armor, Slave Ship, Hard Merchandise)
Thrawn Trilogy (Heir to the Empire, Dark Force Rising, The Last Command)
The Jedi Academy Trilogy (Jedi Search, Dark Apprentice, Champions of the Force)
I, Jedi
The Hand of Thrawn Duology (Specter of the Past, Vision of the Future)
Reference Books for Expanding Knowledge of SW Universe:
For further information on specific and/or technical star wars information head to your local bookstore and browse through some of the "Star Wars: "Essential" Guides. If your interested in anything about the Force, Jedi, Sith, Force-sensitive cults/groups, holocrons, lightsaber combat forms, I highly recommend taking a look at Jedi vs. Sith: The Essential Guide to the Force.
