You guys should be able to get crayfish at most fishing/bait stores in the area. The bait store by my house even has them segregated by size, from 1" to 5". Probably a lot cheaper there than at an LFS. Most bait stores also sell glass shrimp, which would probably be a much appreciated snack as well. Anyway, crayfish are a pretty common bait in the Sacramento area, so you shouldn't have any difficulty finding them CHEAP.