PCTailor,
I use eBay heavily as a marketing tool. I cannot tell you how many new customers i have added, who all came over from eBay. Most folks that i know who shop the net, search eBay first to compare prices. I will usually reduce prices by 10% or so as "eBay specials". This has worked great for two years. Now, my returning customers are responsible for over 35% of my monthly revenue.
As far as the eBay store, I would not recommend it. The items in the store are not searchable when a prospect types into the search bar. (I learned this the hard way, whan sales from eBay dropped like a bomb after i opened my store.)
Now, i usually run 100 auctions at a time. It does get to be a little time consuming to renew the auctions, but the number of new customers has been great.
(Don't forget about listing fees, sales fees, Paypal fees, etc.)
Good luck
Janet