There are a bunch of trackday organisers like keigwins and zoom-zoom and they do a mix of trackdays with instructors who can help you and actual school days at the track (a lot of these are 2 day courses). There are other schools that are just that ie. schools so they have sessions with instructors in a class room interspersed with 45min track sessions to practice what you've been taught.
I've done Reg Pridmore's CLASS (a school) at infineon which was fantastic and they have different levels to suit your experience. I went in the novice group and there was an intermediate and an advanced group and the groups took it in turn to take to the track whilst the other two groups spent time in the class room.
The only negative thing I would say about that course is it is one of the more expensive out there but well worth the price in my books.
I got to go 2up on the back of Reg Pridmores bike for 2 laps - Wow! That was worth the price of admission on its own! :-D
CLASS motorcycle school
I've also spent time with Keigwins - being a trackday organiser there is less emphasis on teaching although there are lots of instructors on the track to give you help if you want and ask for it. This is different on their school days where the format is much more like Reg Pridmores CLASS. A lot of their courses are 2day courses which I like because they are much better value and the second day you tend to be more rested and ready to practice what you've learnt the day before.
Keigwins@theTrack
I'm wanting to do a 2 day course with Keigwins this year (if my boss, my work boss and my bank manager allow!

) Even though I have done several trackdays and a trackday school, I may still go for the novice school because there is less ego at the novice level and the instructors still tailor the one on one portion to your skills. That might be a good starting place for you or you could just plumb for intermediate. If you go to Reg Pridmores CLASS they will promote you to the next level up if they think you're good enough as all the levels are there on the same day.
Hope that helps!