eBay (Auctiva) & website product uploading, & SEO

We have a gemstone, jewellery, & crystal business based in Australia, so a knowledge of gemstones/jewellery and the Australian market would be useful but is not essential. We sell online through our website [login to view URL] (which is hosted by Big Commerce), and on eBay (using Auctiva). We also intend to expand to other online marketplaces like Amazon in the future. To increase sales on eBay and through our website we need people to help uploading products using our templates, photographs, and information which we would prefer to do on a 'per item' basis, and then SEO on our website to help drive sales. Ultimately we are open to a website redesign if it is done with a view to increase sales and ease of use. We are looking for SEO & web-marketeers with experience and a proven success rate. Whilst we currently are limited in the number of items we can put up on eBay, we have potentially thousands of items of stock that we can put on our website and on other web marketplaces. We are also very active on Facebook ([login to view URL]) and would like to use our strong fan-base effectively. Each aspect of our online presence should promote and compliment the others.