I had LASIK about a year ago... I'm 20/20 or close to it in each eye now. Here are my experiences.
1) It requires a lot of up front tests, all of which SHOULD be free. First they have to get a precise measurement of your prescription, and make sure it hasn't changed recently (few years). Then they have to do hi tech photography and scans to determine the shape of your eye and thickness of your cornea. If your cornea is not thick enough such that they can safely take away the amount required, you may not be a candidate. If your doctor does not even measure this, I would say he's probably a quack.
2) The procedure itself is painless though a little uncomfortable. If you can't stare at one spot for a minute or so even if you concentrate, do not go for this surgery. If you constantly look around during the laser shooting, it could be bad news. A little amount of jittering is normal. Usually they give you valium to settle you down as well.
3) After the surgery, you will need a ride home, and probably won't be able to work for the rest of the day due to the valium. You may be able to go to work the next day, depending on what you do, but expect to take it off. For the first few hours, your eyes may feel scratchy. Sleeping often helps this.
4) You will need a lot of post-operative care, most induced by you. You'll wear protective goggles or similar while you sleep. You will have to apply a couple types of eyedrops every so often. You will need to have a supply of artificial tears because your eyes will dry out.
5) If you have really bad vision, you should *assume* you will need touch-up surgery. There's a logical reason for this other than just undercorrection. Think about the cornea, which is shaped like a half sphere. Imagine cutting a vertical section out of the cornea. Suddenly the front is flat. But the natural shape is round. So sometimes your eye will adjust its shape / heal over in order to maintain a rounder shape. After the initial surgery your eyes should be good. Do not be scared if you notice over the course of a couple of months that your eye or both eyes slowly deteriorate into bad vision. I had to wear glasses for a little while, though they were much more attractive glasses than before becuase they weren't 12 inches thick.
6) There are some side effects that are likely. Firstly, if you have night halos with contacts or glasses, most likely you will have them after lasik. Secondly, your eyes will frequently feel itchy or scratchy. Do not rub them!!! If you can't prevent yourself from rubbing them, do not go for the surgery. After several months, they will heal and rubbing will be ok. So, an important consideration is allergies if you have them. My eyes are a lot more sensitive to allergens now, and get red a lot more in the spring. Antihistamine eye drops help a lot (no, they do not make you drowsy). Also, on some days your vision will fluctuate a lot, due to dryness, healing, etc. Don't be surprised if you end up spending a lot on eye medications for the first couple of years. Artificial tears and redness reducers should be readily available at work and home if you have allergies or dryness.
I read that implanted contact lenses were approved by the FDA recently. If your vision is *really* bad, like -15 or so, this might be a consideration. LASIK is approved, though I believe that touch-ups are not approved (though I had one anyway).