Nav, can you help us with a clearer description? And ttell us what you've done so far?
"it is well and truly seized" - what is seized?
Have you undone/slackened the "cog-wheeled strut" (special technical term

) through the small inspection hole in the brake disc body? You have to peer through the hole, which is usually plugged with a rubber grommet to keep the muck out, and shine a torch in to see the little cog, which you then turn with a screw-driver inserted in the inspection hole. This strut holds the shoes open, i.e. against the inside of the drum. Without loosening this strut the whole disc/drum assembly won't come off. By the sounds of things the disc/drum is what you think is seized?
Once the strut is loosened, you can knock the disc loose with a rubber mallet or similar non-damaging implement. It can take a bit of a crack to break the seal of dirt on the hub but shouldn't require major effort. Certainly not a puller!
If it's something else, just shout and we'll try to help

Presume you've read Chris' write-up on hand-brakes in the 90 section stickies?
Cheers,