So I was thinking I'd look for another key fob on ebay to have as a backup and found them pretty cheap. They all say you need to have the dealer program them. I of course don't want to pay them for something that trivial.

I started looking around and it looks like you can only initiate the programming of the key fob by using a GM Tech 2 Scan Tool. This tool costs about $5k. As much as I am tempted to spend about a quarter of the cost of my car on a scan tool just so I can program the key fob that I bought on ebay myself... I really don't want to pay that much for the tool.

Does anyone know of any other tools that would provide the ability to trigger the key fob programming?

at this time no...it's only $45 to program them

You don't have to go to a delaer, most local repair shops have them, they do cost alot of money, 5k for the tool and then about 1,200 bucks for updates every year. About a year ago I replaced my PCM in my trailblazer from pcmforless.com and you have to have the TPS relearned and this can only be done with a Tech2, I went to this little Mom and Pop shop and the guy did it for $10 bucks, the dealer wanted $75 for it, just call around.