WTB Complete LS3 Engine
http://www.apex-speed.com/
Or you can try LKQ...
http://www.lkqcorp.com/home/home.asp
Ebay is a decent source. User fparts has a good reputation on their dropouts.
LKQ is also a good suggestion.
You can find some here in town every now and then but it takes some finger-walking.






