Despite having this ancient thread resurrected, recently there has been an amazing new piece of FREE software for editing audio:
Nice post, Gornot!
Download and tested
Pretty much serves all my needs just as good as Sound Forge. I have yet to figure out some stuff, though, like snapping selections to markers and stuff. Too bad the official website has no tutorials and how-tos, but I've contacted the devs a couple of times now with some questions and they were happy to help.