Before attempting to use these methods, check the crankshaft for burrs and rust and for broken or damaged crankshaft key. Use penetraing oil and try to remove the pulley by hand or with very gentle prying of the pulley.
Some people had success by heating the pulley to expand the metal gear (see photo by mace).
Coinball used a gear puller made to remove a gear off of the shaft of an alternator or similar piece of equipment.
haci corolla used a portion of a valve spring compressor.