Basically, upgrade to 2.1 using Itunes then use Pwnage to jailbreak/unlock. If your on a WinPC I would download a custom firmware thats already built and shift-click restore to it after an itunes 2.1 upgrade. Check out this thread should answer a few questions.
We haz Windows Quickpwn 2.1!!!
Or there are a few in the unlocking section.