yeah, avoid the bike shops, buying used is always financially better. then you can establish a relationship with them. every bike mechanic will work for beer, and its just like anything else, you'll figure it out once you start tinkering with it.
whats the specs on that bike? the components are deff older, do you have up close pics of the cassette, chain, and chainrings? check the freehub body for play, and check the braking surface to see how much more life is in the wheels.