I believe Garza will be available on waivers on Yahoo a few days after his first start on Friday. That's just from my experience in waiting for Hamels, Jered Weaver, Billingsley, Carlos Quentin, et. al. this season. It'll take a while. Start hunting for Garza on Sunday or even Monday, assuming he's still slated for Friday.
It's kinda like the Old Cafe - http://fbc2.freeforums.net