Some of you might find these sites useful. One is The Freesound Project, which is a place for people to upload and download all kinds of sound files. From single bonks and blips, to who ambient environment recordings, to snippets and so on. It's really great for finding special effects for video or audio compositions.
The other site is ccMixter, it's similar but more music oriented. People upload accapellas and beats and are encouraged to take and remix them, mash them, stop, collaborate and listen. It's very community based and seems to be thriving, from what I can tell.
I also should plug Buzz, which is the program I used for almost everything. It can be technical, but because it's open source, it's as flexible as you can program it to be. There are a lot of clever people already at work extending its functionality, so you can find help with pretty much anything you need. Good luck!