I had hard times finding the latest pwnage tool mac version.
Anyway, if you don’t find the latest version, you can still download a version and check for updates while running the pwnage tool.
Enjoy it !
Also, I tried to download “prebuilt” images but it’s hard to know if it has jailbreak, if it has cydia installed and so on… Also, itunes refused to install some of those images. I found it easier to use the pwnagetool with the original firmware and create your own image, you are pretty sure of the result and you don’t wonder “were I really in DFU mode ?” …