I'd search for a source of Internet (such as a WiFi hotspot, open/unsecured network, or hack onto a WEP encrypted router (or dictionary/bruteforce attack my way into a WPA encrypted router)).
If the Internet went down completely (which would literally only be able to happen if the world ended (but the Internet would be one of the last things to go)) I'd build my own Internet; just raid a computer store, get all the routers, and connect them to people far away with fiber optics/existing infrastructure (or just power up the existing infrastructure and do any repairs necessary).