Andy,
The Napa where I used to live had a great selection. Bins and bins of hardware and drawers of the more specialty stuff. Usually, I'd take the old in and get a few extras of whatever I needed. If that's too much of a pain, try the local hardware distributor such as a Fastenal. Check their website, they usually have good prices. My buddy who works next to me had to get a metric threaded rod there for his snowmobile (3 ft length) and it cost him about $3.50. He had plenty left over for future repairs then.
I see there are 3 of them in your city.