The GTO came with both an LS1 and an LS2 in the later models. C5 Corvette had an LS1, C6 started with LS2 and switched over to LS3 in 2008. New Camaro also has the LS3 in it. A basic LS1 is fine to start out with, as most of the parts are interchangeable and pretty easy to come by.
I don't know if this will be your only form of transportation, but the LS series engines get GREAT gas mileage for their size and power. If I lived a little further down south where snow wasn't an issue, I would DEFINITELY be daily driving an LS1 Camaro/Firebird instead of my Civic.