There is a quick little template mod that will add an RSS icon into each forum, next to the "Search This Forum" link on top of the thread listings. I am using it, it works great:
https://vborg.vbsupport.ru/showthread.php?t=104978
As for forum home, you can just put an RSS Icon in your navbar if you wish. Bear in mind that the feed will be indicated in any browser which supports automated feed discovery (FF 2.0 and IE 7.0 both do this) so you don't necessarily need an icon on the page, if people know what RSS is they will see the icon come active.
Dexter...