I don't know a great all purpose finance board. Unfortunately, there's a lot of really terrible advice at most public finance and investing forums and as a beginner it can be really hard to tell who's running on ideology and who's actually done their homework.

The most sophisticated community I know of is the board at Wilmott.com. And I saw that someone tried a nice HN clone at quantly.com, but it sadly never took off.

My personal approach is to build out (and regularly cull) an RSS folder with financial analysis, quant methods and economics blogs. The newsletter from AbnormalReturns.com is a great starting point. Also, ritholtz.com, A Dash of Insight (http://oldprof.typepad.com/) and marginalrevolution.com might be good starters.

http://www.wilmott.com/index.cfm?NoCookies=Yes&forumid=1