It doesn't have to be a big name brand. They charge too much just because there is a tag with a name on it.
In every catalogue and most stores where they sell underwear, they have a smaller section called 'control wear'. You know, tummy shapers and the likes. I got some shirts from there, they look like simple tank tops with spaghetti straps, but they are made out of an elasticated material that holds things together.
I find it's really great because it stops things from wobbling around, and they actually look half decent. Not granny stuff, and they come in different colours and shapes. They have panties there too that are supposed to hold things in place.