Audacity is a free, easy-to-use, multi-track audio editor and recorder for Windows, Mac OS X, GNU/Linux and other operating systems.
"MP3 Cutter Joiner Free is a versatile audio cutting and joining application that lets you cut a large audio file into smaller pieces, or joins multiple audio files into a single one and then saves as the most popular audio formats as MP3, WMA, WAV, etc."
SoundCloud is an online audio distribution platform based in Berlin, Germany that enables its users to upload, record, promote and share their originally-created sounds.