I find the best resource for ecommerce ideas is http://getelastic.com/. I suscribe to a few ecommerce blogs but get elastic stands way out in front.

You should give a link in your posts. I don't know they limit signature links on this site for new users but it can help to have links to your site.

Write a blog which in incorporated into your site and update it regularly. If you can write interesting articles that people will link to, this will help a lot.

In your emails to your customers, include at the bottom: "Do you have a site or blog? Consider linking to our site." Getting links is the best way to not only increase direct traffic but if a variety of sites link to yours search engines will consider your site is of greater importance and rank you higher in search results.

Adsense can be a great way to increase sales. Before you runa campaign, do plenty of homework. It's designed so that people who put the work in and run an effective campaign are rewared and those that do it half a$$ed pay more.

If you are in the U.S, you can post your products on my site. It's free to offer products, your first 2 months of sales are 100% free and the maximum fee for an order is 3.5% which decreases as the value of an order increases.

Notice the link above. If you use anchor like this, google will be more likely to send people to your site who search for a similar term.

Getting links is one of the best ways to increase traffic to your site. Get Elastic is full of ideas for improving your sales on site.