Depends which engine..? You're probably looking for an ls1 (late 90's corvette and camaro and firebird). Unless you are looking for the new supercharged ls9 in the '09 zr1 corvette.
Try http://www.car-parts.com
You can search by distance price, mileage etc. They're mostly used engines but they're cheaper than new ones and you might find a good deal.
