Download sony Vegas HD Pro 9.0 if you're on a windoze pc.
It's what Fobz uses to do the hi def stuff for the P-wrx vids.
Easy to use.
Tons of options.
30 day free trial (fully working version)
You can torrent a non-legit copy (not that I condone it).
I've used it a few times and it's pretty easy to get a decent result.
Here's my first editing attempt with vegas:
http://www.perth-wrx.com/vb/showpost...6&postcount=38