The site offers free auction listings until next year, but it charges transaction fees of up to 5 percent.
Athough the auction site will be announced tomorrow, it already had been launched by this afternoon.
Go's move comes on the heels of last month's announcement that portal sites such as Excite, MSN, and Lycos were forming a network to share auction listings. Portal leader Yahoo entered the auction space last year and is the next largest after eBay, with some 750,000 simultaneuous listings. eBay has about 2.9 million simultaneous listings.
The Go site has about 1,300 auction listings, but more listings will be added tomorrow, said Andrew Hamel, vice president and general manager of Go Network Auction.
Go plans to launch a "multimillion dollar" ad campaign tomorrow to tout the site and will promote the auctions and listings within them throughout its network, including ESPN.com, ABC.com and NBA.com, Hamel added.
Although Go Network auction is a person-to-person auction site, Disney soon will be able to sell goods through the site, Hamel said.
"We're coming in with a strong product and a strong listing base," Hamel said. "We think we can begin to catch up."