If you look at the
http://www.pbase.com/nufsed/drumbrake, in the first picture you will see a red star wheel at the bottom middle. That is an adjustment wheel that will pull the shoes in or push them out. You will want to bring the shoes in and then the drum should just pull off. You do this by inserting a screwdriver in the slot in the back and rotating the star wheel.
It will take a little bit of effort to then pull the drum off due to weight and rust but you will be able to tell if the shoes are hanging up the drum.