I have a 8+ year old Panasonic plasma. Still looks great, but I took the HD plunge this weekend with new 42″ LCD and up-converting yamaha A/V receiver. I ordered everything online.
TG – online is the way to go for you. Shipping is often free and you pay no sales tax. Plus, you don’t have to load and unload it. Get an account on nextag.com and pricegrabber.com, set up lists of the units you want to buy and watch the prices for a while. You’ll see a deal somewhere in there.
The only exception may be Costco, if they have what you need. There is a 50″ LG plasma at costco that is pretty nice for $699 but I had to have a 42″ to fit my existing space.