Just had one last week. Three canals, one tooth.
Kami's right; the pain you're in before is worse. That is, unless you don't have dental insurance. Then the pain from the hole in your wallet might be troublesome. Mine ran $1,000.00 pre Insurance and that's just the root canal (Crown Prep and Crown come after that).
For me, it was worth every penny of my co-pay however as I didn't experience the slightest pain before, during or after (albiet just a little sore from the novocain shots).