I think I've figured out the solution to my particular problem but it still doesn't help...
The billing address has to be exactly the same as what it says on your statement for whatever card you purchase with but it also has to be the same as the address on file for you at the USPS website. That's why people keep posting links to it for verifying your Zip Code.
"The issue might be that your billing address doesn't come up via the USPS website. If it doesn't appear there then it wouldn't work with our systems. Please ensure that your billing name and address matches exactly the address listed on your credit card statement. Any discrepancy in punctuation, abbreviation, or capitalization can cause errors, which might prevent you from purchasing from the iTunes Store. Ask your credit card company to make sure its records are up to date and match exactly what you are entering as your billing information.
What you've been seeing is a new security measure that Apple has added to iTunes. Apple takes the security of your iTunes Store account very seriously. Basically, what will happen is any time you use your iTunes account from a new computer, Apple TV, or a new mobile device you will be required to verify your payment information and re-enter your CVV code. This is a safeguard designed to protect your account against unauthorized purchases.
Since this is the first time you're using your new iPhone 4, you'll need to confirm your account information, including the security code from your card."
My address comes up as unrecognizable for some reason with USPS so it looks like I"m SOL until I find a way around it...
http://zip4.usps.com/zip4/welcome.jsp
There's the link to USPS, hope that helps someone at least