I'll fourth this one too - have been meaning to do a plug for Craig myself, but haven't gotten around to it.
I too knew a lot of the theory stuff, but I even found the theory day enlightening - some of the history and reasoning behind the things done today was great to learn, and looking at the mechanics of those old cameras was well worth it. And if you're self taught there's always gaps in your knowledge (there was in mine in any case, and it's great to know why you do a lot of things you do!), so even if you class yourself as an advanced amateur it's well worth the money.
And how much do you get for your money?? Three full days of tuition from a pro who knows his stuff in a small group with individual guidance on the side, and then an evening to look over things and describe the mistakes and pointers how to enhance the images in photoshop (this bit for me was great - I could do a ton of complicated things in photoshop but I was really missing the point).
Also not affiliated with Craig in any way - but I am definitely thinking about the advanced class sometime next year.