I'm building from scratch as well and the people here and some other blogs are invaluable. I have not flown USAir, and have almost 16000 miles. So my advice, especially if you're still on the fence for credit cards, is to read here (and the blogs of many of the members) and get yourself an Award Wallet account to track all the programs you join. If you need an Award Wallet upgrade code, there's a thread (I forget if it's in Miles Buzz or SPAM).