In library view the layout I'm using has three filters: Genres, Artists, and Albums.
It's easy to see how to get rid of a filter: it has an x beside it.
But how do I get it back once I've closed it?

I'm not talking about the allow/deny filters, I'm talking about the narrow-down-what-you're-viewing filters.
also the program crashes when I try to rearrange them, but that's an aside.
also, I'm not sure what to do with labels: I can add them, but can't find anything else that refers to them. Are they a sort filter or something?