Boy, that's one really huge sentence. Even with no punctuation I did manage to figure out nothing has been diagnosed. Either the starter doesn't crank the engine, which is a starter circuit problem, or it DOES crank the engine but the engine doesn't run, which is a fuel or spark problem, ... Or it starts and runs for two seconds, then stalls, which is an anti-theft problem. "All sorts of parts" doesn't help in any way. Imagine telling your doctor, "I've been to ten doctors and no one can tell me what's wrong, so now it's your turn".
What I would do is repost this question with some information that can be used to develop a course of action. With an engine running problem, we need to know which engine you have. Different engines use different systems, different parts, and have different troubleshooting procedures and common failures. There's hundreds of electrical connections so "the last part that we got" leaves us wondering, WHAT part? Tell us exactly which parts were replaced. Were they diagnosed as defective or just thrown in randomly in hopes you'd stumble on a fix? By now you should have figured out that throwing random parts at a problem is the most expensive and least effective way to diagnose a problem. Having a mechanic look at it would cost less.
Include any other observations that might provide clues, and any other details about the work done up to now. If the battery was disconnected for any of these repairs, include that because doing that can erase the memory from the Engine Computer. Be specific on the symptoms. Does the starter crank the engine or doesn't it? Knowing that will tell us where to have you start with the diagnosis. If it does crank, have you checked for spark and fuel pressure? Have you checked the diagnostic fault codes?
We don't expect you to be as detailed as a mechanic, but so far all we know for sure is you have a '91 Bonneville.
Tuesday, November 5th, 2013 AT 12:34 PM