Thanks for the tip MadMan, I ran apt-get install gstreamer0.10-plugins-ivorbis and now my ogg files play just fine.

How can I tell youamp to ignore scanning certain directories for its database? I did a :/# du -l | grep -i youamp and couldn't find a .conf file to edit. It's picking up all the wayfinder direction sound clips. I only need it to scan a single directory.