ya what bbforks says happens alot
if bleeding it did not remedy things then i would try to de-adjust the master cylinder rod and add more freeplay and then see what happens.
Check pedal freeplay first, if there is none, then loosen the jamnut on the rod and back it off till you have freeplay. Then see if the brakes free up.

If they dont then your problems are probably elsewhere like the park brake or the wheels.
Hope its not the wheels because if they are locked up getting the drums off can be a pain, you'll have to go in through the adjusting hole in the backing plates and manually push the locktab back and deadjust the adjusters to get the shoes to back off enough to get the hubs off.
You can easily check the wheels by putting blocks underneath the mast channels and tilting forward till the wheels leave the ground, then manually try and turn the wheels and see if they are free to turn.