For electronic parts, DigiKey is a good source (www.digikey.com). Radio Shack will have a lot of the common parts on hand and will also have some great little books on electronic projects. If Radio Shack doesn't have the parts that you are looking for - ask for their catalog. They have a lot of parts available for special order.

[This message has been edited by Jon68 (edited 08-31-2000).]