Rebuild Cost
Where do you live at?
Are you going to do a stock rebuild? If so it is cheaper to get a replacement motor from like SDPC. Either new or rebuilt by GM.
If you plan on a little spiced up combo, with like maybe a cam or forged with cam etc..
Your option are endless.
On average you can get a forged shortblock for around $2800>3000.
Piece of advice, research carefuly, avoid cheaper options that are too good to be true, If you get yours rebuilt, do it at a shop that builds LSx on a regular basis.
http://www.sdparts.com/
Most street cams don't need any modification to install with the stock heads. But, it is always a good idea to have a tuner tune the car no matter how small a cam you run.

