That looks like a fine set up to me. The 50 f/1.8 II is a good sharp lens that's pretty fast. The new 18-55 3.5-5.6 IS is a surprise, the initial tests on photozone show it to be very sharp and a marked improvement over the original kit lenses. Definitely step up to the IS version.
The only thing I'd change is to get two 2gig cards instead of one 4 gig card. If one card corrupts for whatever reason you'll still have a back up card.

B&H is probably tops when it comes to etailers and are a sure bet when making camera purchases. If you go elsewhere bargain hunting, make sure you are buying from a reputable dealer, check out this site's dealer feedback forum and resellerratings.com for information on your chosen dealer.

I am a naked lens guy and only use filters if I need to. In the digital world filters have nearly become obsolete, most of the effects of filters can be reproduced in post processing. A polarizer is about the only effect that cannot be reproduced.

I think most camera stores are well aware of the internet and the pricing there. I too am willing to support local shops but not at a huge price increase.