I officially approve of and recommend this blog post:
artologica: If you want to sell on the internet, you have to be on the internet
It's about internet marketing - but not the way you think. The gist is that you can't just put a photo out on the internet and assume people will come running to buy your wares. You also can't broadcast onto twitter and pinterest like a robot, reading nothing, and assume people will read what you're saying.
So get out there, people! Be the kind of internet user who you enjoy hearing from, it'll do you good!