Kristine:

I used ice baths last year while training for Philadelphia. After my long runs, I would take about six frozen bottles of water and climb into the tub with them with my shorts on, turn on the cold water only, and grin and bear it. I let the water fill just until it covered my knees and would sit for 10-15 minutes. I found this was much easier than filling the tub and jumping in once filled. It is really not as bad as you may think. I had very little soreness after my long runs and seemed to recover much quicker than without the ice baths. Good luck.

The Newbie Wiki link says that ice baths should be done immediately after the long run for maximum effectiveness. Are they still effective if done a few hours later?