Big Block Advice?

I honestly am not sure of an exact number for my budget. Obviously, I'm going to want to build it on as low of a budget as possible. I'm hoping to have a part-time job by the summer, but I don't know about that with the way the economy is right now. I've got motocross stuff that I'm probably going to sell, so that money is going to go towards it. That should give me between a $1200-$1800 budget for right now.