What is the best way to get eBayers to submit their auctions to me for free advertising?

Our site AuctionGab.net currently has more than 500 eBay members that use our free services. We advertise their auctions for free. But are now looking for more eBayers to submit their auctions to us for free advertising.

I have been trying to spread the word on free auction advertising through Yahoo Groups, but am relatively new to this.

Suggestions?

Thanks!
Gabber

http://www.AuctionGab.net