In the city: nicer areas which have many apartments are Squirrel Hill, Point Breeze and Shadyside, Highland Park. Not quite as nice but still very livable are Oakland and Bloomfield. Avoid the Hill District, Lawrenceville, East Liberty.
Outside the city in the suburbs, avoid Wilkinsburg and Mt. Oliver. As miniMUNCH (who still owes me a beer, by the way.

) said, the transit system is pretty good. If you live South of downtown you could use the light rail system. You could save a lot on parking if you took the bus or light rail into downtown. There are quite a few park-and-ride lots in the suburbs.
The highway going north out of downtown has an HOV lane which helps the buses make decent time.
If you live in the city, there's a pretty big wage tax, so know for sure before you make a choice.
darkjester, what South Hills neighborhood are you moving to?
The apartment guide I picked up at work is called "Pittsburgh's Apartment Source" (August issue). If that's one you could use, PM me and I'll mail it to you.