Right, it doesn't take a genius to work this formula out. More eBay store visitors = more sales.
Make sure you provide a link to your store in every auction. Don't just expect people to click on the link eBay provides. Make a link and ask people to click on it and they will. How many times have you seen the term 'please view my other auctions' or 'visit my eBay store for more bargains' I bet you've clicked on those links sometimes too? I know I have. It’s all about encouraging the person viewing your auction to do what you want. After all, if they don't click on your link what have you lost? Nothing.

Another way to generate visitors to your eBay store is through email. You should include a signature in your emails. Something like the one below. In outlook express go to tools, options then signatures and set one up.

================================================
Get 100s of fantastic items starting at only 1p at my eBay store.
Simply visit http://stores.ebay.co.uk/PlanetSMS
================================================

Notice how I use = as a border, this makes your signature stand out.
Always mention you have other items in your store and always provide a direct link at the start or end of each listing.
Also, use the auto invoice eBay selling manager or PayPal provides (use one or the other, not both), again mention you have more items for sale in your store. Also mention this in your winning buyer emails.
If you can set up an auto responder. Have it say something like:-
Hi. Thanks for getting in touch, I have received your email and will respond soon. Then include your signature.

***********************************************************************
Get 100s of fantastic items starting at 1p at my eBay store.
Simply visit http://stores.ebay.co.uk/PlanetSMS
***********************************************************************

Notice this one has stars (shift + 8) Experiment and find out what you like best.
Under no circumstances should you spam any past customers. I'm pretty sure you hate receiving spam (unsolicited emails) and so will your past customers, and by spamming them you will probably have the opposite effect of gaining more custom. You may also be reported to your internet service provider or eBay.