Recently a business colleague Matt Freedman facilitated a discussion on at which there was a general concensus that there is a lack of myspace type networks for business. Matt indicated that ecademy.com comes close but is very cluttered and you have to pay for a lot of the features.
In response, Matt decided to kick off a social network for Australia entrepreneurs. you can find it here http://australianentrepreneur.ning.com
Personally I am a member of linkedin.com and have found it to be a great tool for connecting with others and allowing me connect with others in coaching and communications ie it is a connection network not a social network. See my profile http://www.linkedin.com/in/heidialexandrapollard
Join in either of these communities and contribute and share with others.