they sell pulley holders:
http://www.google.com/products?hl=en&q= ... 1&ct=title
I've always had luck with a PB blaster and an impact though.
you can always block your flywheel from turning which will keep your crank pulley from turning.
You could even take out a spark plug and get a long bolt of the same thread and screw it in right to where your piston is approaching TDC and stop the piston from moving up and stop the crank pulley from moving. Just be sure to take it out before cranking the motor!
Once the crank pulley can't turn, get a huge breaker bar or use a pipe over a smaller one you already have to make a longer bar for more torque.