Art auction website promotion

Background I have started an artwork auction website ([login to view URL]) in Australia that is looking to attract university students and other novice artists from across the world to register and sell their artworks online. The aim of the website is to provide quality art to consumers at affordable prices. Project - Website promotion Minimum requirements -100 genuine new members to register on the website. -60 of those being amateur artists who each post a minimum of one piece of artwork. -The other 40 of those being possible art buyers. Generating a minimum of 100 bids. I need to attract amateur artists above the age of 18 to register and post their artworks. They can be from any country. They can be current ebay users. It is worth noting that it costs users a small fee of three Australian dollars to register a piece of art (equals approx 2.30USD). I also need to attract people whom are interested in collecting or buying art. They can also be current ebay users. Payment will be made upon fulfillment of the minimum requirements. I am not concerned about how the new members are attracted as long as they are genuine and I will be checking member details and site stats. The key aim is to encourage artists to persist with the website. Once I have met my startup costs registration fees will drop. If this is the challenge you've been looking please for let me know. Thanks, Mark