Does anyone know of a site which will tell me IP blocks assigned, broken down by country?

Call it jingoistic if you want, but 90% of suspicious scans and attacks on our servers trace to IP's registered outside the country (we're in the US). I want to block all of it, since our company does 100% of it's business in New York State, and every single client client we have or might have is US-based.

I'm tired of reading logs, clipping log fragments, and e-mailing them to abuse mailboxes all around the world. I'd prefer to just reject or drop anything coming from outside the US, period. It's never going to be legitimate business traffic for my company.

- Qualm