I think depending on HOW many sites you have, it may be better to pay a lawyer. If your running something VERY serious like a hosting biz, I'd reccommend a lawyer. Just because WHEN legal actions are taken place, you don't want to deal with hassles.

If it's something small like a forum that's in low stages, I would go with Lesli's idea and write it myself. I'm sure some local lawyers shouldn't be that expensive, especially to write up a TOS agreement.