Thrawn trilogy most defiantly, Heir to the Empire has just received an Anniversary Edition with some nice extras in it so thats a good place to start. Outbound Flight aswell once your done with those, and well pretty much anything by Zahn.

Palp knew of the vong and had to prepare the galaxy for them, how things were it didn't stand a chance and what better way to get the galaxy ready than to start a war to unit the galaxy to stand against the vong when they attacked and while he was at it take the jedi down, two mynock's but with one force thrown stone.