You need to step outside QVC. Bare Minerals are bringing out a liquid foundation later this year I know.
I would go to Boots and ask them to do the machine thing and match a colour for you, tell them the coverage etc you want and they will give you a sample to try.
Personally I don't like Boots No7 makeup but that is not to say it will not work for you.
Donna, do you use BM? I gave up using it dry years ago - have had much better luck mixing the minerals with my fave moisturiser. I always manage to look too dry otherwise (though I did used to use a finishing spray and even a warm, damp washcloth to finish). Applying with a BeautyBlender or one of the knock-offs that are circulating these days makes it flawless but very natural looking.