I have .WMA & .WAV files that I would like to take a section of and put into a new file, containing just that section. I would like to be able to do the same with an .mp3.

If that cannot be done, it would also be useful (though less so) to be able to open one of these files, and then, through clicking something (probably a button, hmm?), to be able to mark the start & end of a position in the file that I would like to play in a loop.