Any idea where I could get 3-4 toilets for really cheap?

Yes! Look for salvage places and junkyards. You might also want to try just calling plumbers. I know a few, and they always have old toilets and other random junk to get rid of, which tends to sit around in their backyards until the disposal truck comes to collect it. They'd be glad to get rid of it without paying.

What're they for, by the way?