fj--
you can do all that and a whole lot more. Since I've been trying this sort of thing myself lately, I have a basic knowledge of this stuff. I tell you what I know and then maybe someone else can help you make the program really sing.
1. Record label field. Go to "Tools / Options / Library." Under "Library Fields" select "Add". Give it a name, make it a "default" field and keepit a "string" field. You now have your Label field.
2. Right-click on the panes and select "edit view scheme". Here you "Add" the label pane and move it up in priority. Re-arrange genre, year, etc, from top down. Now you can visually sort using the panes, from left to right.
Far more sophisticated searches are possible, using smartlists, elaborate string arguments, etc. For me, that stuff is way beyond my attention span. This will have you good to go in minutes.