Kraynick's Bike Shop is a diamond in the rough... even if the diamond itself seems rough. It's messy sometimes and definitely cramped. But if you can deal with that, it is a great resource for Pittsburgh cyclists. There are six racks in the back where patrons can work on their bikes, and Gerry will sell you the necessary parts at discount rates.
Many times I've gone in to fix "just one quick thing" and then three hours later I finally leave. It can be intimidating if you don't know much about bike mechanics, but other people there are usually helpful and friendly, and though he doesn't always radiate warmth, Gerry has helped me with a number of issues.
In short, a great resource and way to learn a lot and save money if you have the time.