I’ve come up with a list of ten main networks I think you should build profiles on. Here they are:
1. Facebook pages.

Go to Facebook and create a musician page. You can put all your music, videos and events there. It’s a really neat looking platform. You can also have a discussion board and host conversations. Start passing the word around and get your fans on that page.
2. Twitter.

As a micro-blogging platform with just 140 characters, Twitter is short, sharp and cool. Build a following there, host discussions and let the people know what you’re up to in life.
3. Myspace.

Myspace is a musician’s favorite, although I don’t really like it. I think it’s great for networking with others in the music industry, musicians and entrepreneurs, but not great for growing your fan base with real people who are not musicians and will actually buy your music. Still get a profile if you like.
4. YouTube.

Get all your gigs recorded. Even record your recording sessions. Put up as many videos as you can and share them on all your other profiles. The key is to create an intertwined network with all your sites. I use blip.tv for videos on this site instead of YouTube because my videos are longer than 10 minutes.
5. Flickr.

This is all about photos (and now videos too). Put up all your photos and again link it around to all your other networks. Create an intertwined network all about YOU.–As you can see, I’ve given you a few options here but if you picked it up, they are all to do with different mediums - i.e. blogging, photos, video, text, etc to get people thinking and attracting all kinds of people.
Have any of these worked for you?
Do you know any others which you recommend?
Share and let’s discuss…
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I agree with your assessment and would add that depending on what genre/lifestyle you are operating in, you should probably also include an active network in that space. For example, if you are a soul music artist, you should definitely also be on SoulCommune.com. Find one within your genre/lifestyle that is the best fit.
I would recommend two things. Create your own website as well with links to all the social networks.
Also, post your music on http://www.startmysong.com. There your music will be pushed out to the social networks for you and you can link your artist account back to any of your accounts above for people who like your music.