Aside from the annoyance of having your face numb, there really isn't any pain in getting drilled in my experience. I even had an implant put in.
It's interesting that you mention this because I just had a filling done yesterday with a Waterlase. It was entirely painless and did not require any novacaine. I got the impression from my dentist that if the decay is deep enough that novacaine may still be necessary ("This looks shallow enough that I don't think I need to numb it, but if you have any discomfort, let me know.").
It feels like a rapid pulsing and it doesn't give the grinding feeling or heat and burning enamel smell that drills give. The
Waterlase web site briefly describes how it feels, and that's an accurate description.
I would also caution against just picking a dentist out of the phonebook. Get references from people you know. Nothing worse than a crappy dentist, no matter how much technology he has.