I noticed some people post entire songs while other post excerpts. Is there any fear of having your material stolen or used without permission? I guess that's a risk of putting anything on the internet. I was just wondering how others dealt with the topic (hope this it's ok to post this here). Thanks!
I have yet to have any problems with work being stolen or something so I feel pretty safe...
Technically an original piece of music is copyright from the moment you write it. However, if someone has stolen your work and you want to sue them, you'll need to have proof you wrote it first, and the most secure way (if you live in the US at least) is to register the copyright. See http://www.copyright.gov/
I regularly register copyrights, so I feel extra safe.