It's a pretty involved process that isn't for the uninitiated (full instructions here) but with a little patience, you too can have root access on your stock Froyo'd EVO. Easier methods and probably even one-click apps similar to Universal Androot (which doesn't work on the EVO, by the way) should be available soon, so if command line prompts make you nervous, then you might want to wait. There's always an element of "proceed at your own risk" with rooting, so if you don't know how to get out of a sticky situation or think adb shell is something you find at the beach, then it's better to play it safe and hang tight until a simple root/unroot app method is released.
For everyone else, root on! Anyone do it yet?
Thanks to everyone who sent this in!