Here's a good place to start
WARNING: Viruses on the network you should be aware of


What you should know about wma files
mov files
.wma, .wmv & .mov files are ones to be careful with, see the links above. You can add these extensions to your keyword filter (tools > options > filters) to prevent them appearing in searches.

Always check a video file with Bitzi before download. Audio files aren't rated too often. Check program files with Bitzi too
How to use Bitzi

And some info about downloading audio, much of this advice also applies to video
How to find music

Sorry for so many links, I don't mean to make your head spin!!