What are some cost effective ways to market my business online?

[Steve]

Promoting a site through Facebook isn't a good business model, instead you need to make sure your website has proper coding for SEO (Search Engine Optimization), so that if someone searches for jewelry your site will feature on the first page of the search engine.

To make a successful site, you also need good quality incoming links, try linking to suppliers or other jewelry sites, you'll need to contact their webmasters/owners for this.

Also use advertising sites to post free links to your site, e.g. for sale pages of classified ads

If you have the time to write articles, in other peoples blogs/forums, always post a link to your site in your signature. Selling stuff on eBay should also give you some opportunities.