Im doing mine at the mo. Passed me theory test couple of weeks ago and started my practical last friday. Got my test booked for this thursday so with a bit of luck it will go to plan. I'd definatly recommend getting the dvla theory test book, its a bit different to the car test as you have to score 51 out of 60. Luckily I got 59 but there were a few hours spent at work going through the book. Medical cost me £80 and you need to take a D4 form along with you form it which you can download off the direct gov website.
Actually, here it is
http://www.direct.gov.uk/en/Diol1/Do...ng/DG_10031645
Got all the forms you need on there.
Once I had everything to send off for my provisional it only took the dvla a few days to send it back to me updated which I was quite impressed with.
Hope that helps