boy do I share your frustration... that is what is was like when I first was bike shopping.
"Sure try the medium, we'll order you a small, but you have to buy it without trying..."
No thanks. Keep calling around until you can find some thing to try that fits. It may require a road trip. Don't get stuck on one brand, either; there are lots of cool bikes out there.
You might call around too, expand the search area. Watch Craig's list, etc.
I finally found a nicely equipped, very lightly used bike being sold by a female lbs owner...
Patience, the right bike will come.