There was a mistake in the title, I've now found a download for the the 5.1.1 firmware. Here:
http://www.redmondpie.com/download-5.1....official-links/

Can I just use that to update my 4.3.3(8J2) to 5.1.1 and jailbreak that unteathered? Is there any problem with that plan? I was under the impression you needed to upgrade via itunes for some reason? Is that a fact?

I just need to get to iOS5 to be able to run all the apps that require it. I am trying to avoid going to a tethered 6.1 jailbreak.