Thanks for the info, both of you. I'm more worried about getting him to send my gun than getting him dealt with on gunbroker; I'll take that approach when I get desperate (but I probalbly will very soon). I feel like I have to persuade, threaten or trick this person into doing something he should have done weeks ago, and that is not fun.
I've bought well over 100 items on eBay myself, and only one of them was a ripoff, so I can believe that part about 99% of transactions being good. However, I've never bought an item for over $100, so this seems like a whole new game; especially when there's one more person to deal with. I started out doubtful that I'd get my item before my big weekend and now I'm worried that I'll never get the item, period; so my expectations haven't been met at all, it makes the idea of buying a gun online or through the mail look like less of a good idea to me.
Whatever happens, I know what I would do differently next time, and I thank you all for your advice.
One last question, if I come to a point where I know I'm not going to recieve my item, what do I tell the FFL holder? Does he need to know that the item isn't coming back?