I admit it. I think the interface of iTunes 11 is a bit…counterintuitive. Clunky, even. As soon as I installed it, I turned the old sidebar back on (View > Show Sidebar), and I sometimes still think it's not very user-friendly. That said, I find customizing my view has helped a lot. This trick isn't new to iTunes 11, mind you, but it's never seemed so necessary. No offense, Apple.
So to change the way your stuff is organized, go to any source list. Those are the buttons across the top of iTunes' window, labeled Songs, Albums, Artists, and so on.
Then press the keyboard shortcut Command-J (View > View Options).
Depending on what source list you've chosen, you'll be able to change different things after you do that. For example, within Songs view, you can quickly pick which columns show up and which one is being used to sort:
For Album view, here are the choices you get:
I like sorting mine by title instead of by artist, so that was huge for me!
Under Artists, you can even change how large the album art is:
And so on. It's useful to mess around with those settings, as you never know when—BAM!—you'll find exactly what you're looking for, and iTunes will suddenly become a happy place to be again. I kid, I kid. OK, mostly I kid.