the only one i know of is bravenet, i think? if you have a hosting plan most come w/ options in your cpanel to have a forum.
here's a hint for anything you need to find relating to websites... google it.
Is there any free way to add forums to a website? I don't know any programming (apart from very basic html), so I want it to be simple.
Thank's for your time,
O.R.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic