Glad you brought this up Laura. I've been thinking about getting us something more sophisticated too! We use a combination of a Google spreadsheet and a notebook in the shop for a lot of things. When someone buys a bike in the shop, the shop manager for the night will write it down in the notebook. That's also where our volunteers night in for the night. When customers sign in to the shop, it goes to our Google spreadsheet. As far as inventory goes, I think that's in the notebook, or at least our "front space" or more expensive bike are. I must admit, most of the bikes that are in the back and need repair, along with all the hodgepodge of parts in the shop aren't really inventoried.
From what I've heard, previous people have tried to tackle this issue for us before, but haven't had much success. The notebook and Google spreadsheet work okay, but in my opinion it could be improved. One thing I've had to keep in mind is that not everyone is technology savvy when it comes to this stuff. You can have the fanciest software in the world, but it doesn't do you much good if no one can use it!
Kat
Sopo Bike Co-op
Atlanta, GA