I sat in on some of the Virtual Labs that Etsy had while they were in Portland. One of the topics was Engagement Marketing. The definition of which is building an audience with ongoing relationships.
Approach people as friends. Don't let your first interaction be about selling your creations. Earn the right to market to people. People who tweet, read blogs, visit facebook have a great tool to turn your "pitch" off with the ease of a click, their mouse. We are all so overwhelmed and over communicated with stuff... if people feel that you are not sincere or authentic they will just turn you off. It is so much harder to win people back then to gain their trust first.
People value little tidbits of helpful information. Rather then tweet "just listed," or updating your Facebook or blog with your wares share something useful. If you blog, why not do a tutorial. It doesn't even have to be in your area of expertise. Maybe you have a recipe that you really love. Or, a hint on the best place to purchase ink cartridges (sorry I couldn't think of anything else). Be the person that the audience seeks out for valuable information. Once they think of you this way they will listen/read about your creations. Even better, they will give you feedback on what they think about them!
Have a great 4th of July!