I thinki all of the programs mentioned above are pretty good programs. Main thing is what are you going to use it for. I have Sound Forge 6.0 and also Noise Reduction 2.0. Excellent programs. I also got a free version of Cool Edit Pro Special Edition with my Mia sound card.
I think if your best bet is to download some of the programs and try them out. See which ones you like. I have one very expensive program that I don't like at all and probably will never use.
Definitely try out the free demos..you can't go wrong. Sound Forge has a very good forum as well as Cool Edit. The old Cool Edit forum pre-Adobe is still going. It is called AudioMastersForum.org this is a very excellent forum to get help.
Best
Scott