blockquote>"redsn0w 0.9beta3 results were good, may as well take it out of beta: http://is.gd/7ppQO (new: ipt3G and IPCC tethering)"
This version of redsn0w supports all iPhone and iPod touches running the 3.0 and 3.1.2 firmware. If you need to perform a carrier unlock on your iPhone 2G, redsn0w can do that for you but for the 3G and 3GS you must use Cydia to install blacks0w for baseband 04.26 and ultrasn0w for baseband 05.11. And yes, for late model 3GS devices you are still limited to a tethered jailbreak.
For the full details and download links be sure to check out the official redsn0w 0.9 wikee.