This is a query for any teachers or anyone in a similar position...or anyone at all who can help.

Nearly eight years after sitting the first lot, I want to do another A-level (in maths). I have a friend who has offered to explain and tutor me. It's not a completely alien subject given that I'm working in a Computer Science department, so I don't feel the need to enrole with a college or attend lessons (ha! such optimism!!).
Questions:
Is it possible to sit A-levels as an independent, private candidate? I mean, do you just pay-yer-money and take-yer-chance in an exam sitting?
If so, what happens about things like coursework?
Anyone know much about exam boards? Which would be the best to do? I've got information on the EDEXCEL London board, and they have a syllabus online, but perhaps that's not well-recieved? I don't know how I can judge that.

Anyway, the reason I actually want to sit an exam is that it'll make me focus and _have_ to learn stuff rather than my usual trick of losing interest and/or bluffing it. And it'll be fun (misplaced optimism no. 2).

Any light on the subject would be gratefully received!