Open Source Address Scrubber?

Question

I have set of names and addresses that have been entered into and excel spreadsheet, but the problem is that the many people that entered the addresses entered them in many

Answer 1

I actually work in the address verification industry... Jim's answer is a smart accept. Unfortunately for those of us with low budgets, official USPS data is pricey and the systems are complicated. (I know by experience, since the company I work for, SmartyStreets, provides address verification at lower rates than most.)

The best I can do here to help is recommend a low-cost/free alternative (depending on your volume) such as LiveAddress, where for a list of addresses there's no minimum purchase, and the API is super-cheap and super-easy, comparatively.