Question: We're deploying a new website, hosted ourselves. Short of getting in white hats how would you go about penetration testing from outside the network?

Answer: 
the whitehat consultants i've seen come in & use [this tool](http://nessus.org/) then send you a massive bill.

Take a look at [OWASP](http://owasp.org) (Open Web Application Security Project) they're very informative & free! they have a very detailed [pen-testing guide](http://www.owasp.org/index.php/Category:OWASP_Testing_Project#OWASP_Testing_Guide_v3) that you must look at.
[Nikto](http://www.cirt.net/nikto2 "Nikto") is a nice start to look for well known vulnerabilities. Works on Windows and Linux, etc. Simple enough even for noobs like me :)