Here are step-by-step tutorials that will guide you through all the process of jailbreaking iOS 5.1 and iOS 5.0.1 with sn0wbreeze, redsn0w, pwnagetool and absenthe:
The iPhone Dev-Team has updated PwnageTool with support for the iOS 5.0.1 untethered jailbreak. PwnageTool lets you easily create a custom ipsw for upgrading to iOS 5.0.1.
Unlockers can use custim firmware to preserve baseband version and unlock with ultrasn0w or gevey. Depending on your device you can also configure the ipsw with boot logos and Cydia packages.
PwnageTool 5.0.1 supports iPhone 3GS, iPhone 4, iPad 1, Apple TV 2G, iPod Touch 3G, iPod Touch 4G.
You can download the new version of PwnageTool 5.0.1 from here.
Redsnow is easy to use, it is available for Windows and Mac OS. As usual for unlockers – do not update to 4.3.3, use PwnageTool (MAC) and Sn0wBreeze (Windows) to preserve the baseband.