I'd like to set-up a forum, but I need to know where to start...

Hello everyone,

I'm running http://pie-magazine.net and we're setting up a new Members only area called Pie PLUS+. It's a free sign-up but I want to get people interested with some additional features.

One of these is a forum. I've tried a few plug-ins already but I'm not very skilled in working with them - at all. I realise I'm going to need to do a fair bit of code-based editing as my chosen theme doesn't seem to respond very nicely to the forum plug-ins I've tried, at least not on basic settings.

So, my question I suppose is, where do I start? Are there any helpful video tutorials out there?

Any help is welcome!
Thanks,
Ben