A good starter is "Mermaid Ave." - they're a sort of folksy rock band from the mid-west, but it's about the best pensive-white-boy music I know, short of Nick Drake - and yet it's very cheerful and upbeat, even as it's thoughtful. Wilco (and Jeff Tweedy, the front man) tread the line of being introspective and sensitive without falling over into lugubriosity or depressiveness.
"California Stars" got me on the road and out here to the West Coast. "Someday, some morning, sometime" helps me believe not all love is doomed, and that it's okay to miss people you care about. "Way Over Yonder in the Minor Key" makes a ballad out of being a weirdo.
Good stuff, give it a listen.