I'm looking into getting an upright bass. Any suggestions on what to look for in general? I guess i'm looking for a "starter" type, nothing too pricey but something good to learn on.

With a starter bass, plywood back and sides are o.k., try and get a spruce top, (cheap chinese basses use pine, stay away). Make sure it has an adjustable bridge.

This would be a great start for you, and it's in Denver...

http://cgi.ebay.com/Vintage-Kay-M-1-Blo ... dZViewItem

actually, that'd be a great stopping point too, I used to have a 1952 Kay S-1, and it was slamming. I love my NS-Design electric upright, but nothing sounds quite like the real thing...

Phil's the man.

Anything acoustic, be it guitar or bass, needs a good top material. Sides are really just structural, so as long as it's strong and doesn't absorb sound it's fine. But the top plate is the "speaker" for it, and the way it vibrates in response to the strings has everything to do with how the instrument winds up sounding... "vibrant" vs "dead." Pine just doesn't respond like spruce, or sitka fir... much tighter grain and better stiffness.