Who makes all these LCD sets?

I am ready to purchace a 32 or 37 inch LCD TV

Westinghouse, LG, Polaroid and the big names SONY, Toshiba, Panisonic,

They can't all be building flat pannels. Who makes what? Is there
any difference between any of these sets? When I see them on display
they all look good to me. Some a bit better but not that much.

If a SONY and Westinghouse 37 both look the same why should I drop
another grand for SONY?

How would a person get service on an LG set 3 years from now?