Haven't read all other responses, but I really want to say that (just like with a vaginal birth, in fact - and I've had both - ...) it feels like the best thing in the world. Above and beyond everything else, it is the moment when a new life enters the world. Not just any new life, but your new baby. Anything else you feel - all the physical sensations - will be as nothing, because your baby will finally be with you. Try to enjoy it!
Having said that, if you want to know about the physical stuff, this is what I remember (from nearly 8 years ago now).
The injection for the spinal block stings a bit (like a bee sting) but takes effect really quickly. They test whether or not it has worked with a very cold spray which they spray on you and ask if you can feel it. you should be numb from your nipples to your knees.
I'd been in hospital for a long time before mine, and the midwife shaved the area one I was numb, but if it's a planned section and you're going in from home it would be nicer to do it yourself (or get someone to help).
Be prepared for there to be a lot of people in the room with you. I had two anaesthetists, the surgeon, his side-kick (might've been a student, I'm not sure), a midwife, a theatre nurse, a paediatric nurse and Uncle Tom Cobbley and all... (Not sure if I had more than is normal because I'd had a problematic pregnancy, but the room was full!)
The person you'll have most contact with is the anaesthetist who'll be up at the head end with you and your partner. Mine kept us chatting during the first part of the operation (while they were doing the incision), but backed off totally once dd arrived so that dh and I could enjoy holding our baby.
There is a certain amount of rummaging, which you can feel happening, but without pain. Then, just before the baby is born, the surgeon (or side-kick) pushes down quite hard on the top of your bump. This is to push the baby down, and when you feel it it means that your baby will be with you very soon. A midwife warned me about this the day before the op and I was glad I knew it was going to happen, because it did feel quite 'forceful' (again, though, definitely not painful).
There is also a hoover thing (??) that they use to suck out the waters. Can't remember, though, if this came before or after the pushing!
You should be able to hold your baby while you are sewn up.
I was in recovery for about an hour. My main memories are (a) a delicious cup of tea (had been on nil by mouth since the night before and was gagging for a cuppa!) and (b) the horrible flobby feeling in my stomach when the feeling started to come back. This is not unlike the feeling you get after a vaginal birth, though.... just saggy skin!
I got out of bed the next day. And my recovery was pretty easy. Keep moving - it's painful at first, but it's the best way. I had morphine injections (x2) on the day of the op, but hated them (made me feel out of control and scary). After that had paracetomol and codeine initially and then just paracetomol, plus voltarol. I found the pain very manageable. At first I had the feeling that my top half wasn't properly attached to my bottom half (iykwim) and so moved around very gingerly, but that soon got better.
I was in hospital for a week, but that was because my dd was being tube-fed and I wanted to stay with her for as long as possible. (In the end, I had to go home without her, which was a bit heartbreaking.) However, had it not been for dd, I'd have felt OK to go home (as long as there was someone with me to fetch and carry) after 3 days or so.
Hope this helps. Remember what I said at the start before all else! Oh, and good luck!