For sale: 20,964 party goods and games, $400; 1,000 belly rings, $375; 5,000 cellular antennas, $850.

Americans love a bargain, but these deals aren’t for Joe Consumer. The products are sold only in these huge volumes. In each transaction, some of the merchandise may be damaged or without packaging or instructions.

Welcome to the $100 billion market for returned and surplus merchandise, which is booming, thanks to the Internet.

In a field once dominated by large, local liquidators, even small businesses and solo entrepreneurs are snapping up bargains in bulk and reselling them from their own Web sites and on eBay. This free-for-all is driving up prices, which could put some surplus wholesalers out of business.

Retailers and manufacturers have always had to unload excess inventory, representing 3 percent to 4 percent of revenue. Traditionally, they sold the goods for pennies on the dollar to liquidators, who turned around and sold the goods from warehouses to entrepreneurs who resold the stuff at swap meets, outlet stores and second-hand shops.

It was a geographically confined, large but inefficient marketplace.

The Internet is especially good at introducing efficiencies into such markets, said Bill Angrick, chief executive of Liquidation.com, a $60 million liquidation service that conducts 12,000 bulk online auctions monthly for major retailers, manufacturers and the U.S. Defense Department.

Suddenly, the market for unsold goods is global.

The previously mentioned deals were recent offers on Liquidation.com, one of a handful of venture-backed survivors among 1,100 Internet surplus-goods wholesalers from the dot-com boom. Unlike most of his competitors, Angrick doesn’t buy the goods; he takes them on consignment.

But because he handles warehousing and shipping, breaks the goods into smaller lots and provides other services, Angrick gets 50 percent to 200 percent higher return for the sellers.

“I think companies are very sensitive to extracting more value and using best practices,” he said. “It would be embarrassing to leave money on the table (when unloading surplus merchandise) these days.”

Even land-based liquidation wholesalers, like Rhino Mart in Santa Fe Springs, Calif., are moving onto the Internet.

Fullerton, Calif., resident Drawlon Tsang started selling pepper spray at swap meets to earn money while in college. One customer bought large quantities and then sold the cans at a small shop. So Tsang also moved into retail, then discovered the simpler, less labor-intensive bulk wholesaling of closeouts, returned goods and salvage.

Tsang, who looks 18 but is 31, now operates a 50,000-square-foot warehouse and Web site, www.rhinomart.com, which accounts for about 20 percent of revenue.

Ironically, growing competition is pushing up prices and sending Rhino Mart back into retailing. Tsang soon will open outlet stores in La Habra, Calif., and Santa Fe Springs. Currently, if he can’t sell in bulk for a higher price, he loses money. The stores will provide an opportunity to recoup his investment, even though labor costs are higher.

Wholesale still will dominate Rhino Mart’s business. But even the online buyers want to talk by telephone with a Rhino Mart representative about the contents and condition of the products, he said.

Because all sales are final, “We ask them to sign an agreement that includes our disclosure about what they’re buying,” Tsang said. “If they buy it in person, they can see it and inspect it.”

Also, Tsang’s business depends on fast turnover of merchandise. If it takes him two to three hours to post on the Web site photos and description of a palletload of goods, it might already have sold from the warehouse.

Still, a growing number of entrepreneurs are jumping into Internet bulk sales.

About a year ago, eBay started noticing wholesale lots among its auctions, spokesman Kevin Pursglove said. In October, the online auction site opened a wholesale category and now has about 36,000 auctions of bulk merchandise going every day.

The wholesale category sold $20 million in 2002 and is on pace to sell $45 million in 2003 for eBay.

Angrick estimates that 30 percent of his 110,000 buyers are eBay power sellers (selling more than $1,000 a month). One is Jacques Stambouli, a Harvard MBA who sells department-store returns online through Via Trading in Los Angeles.

“This industry is so under the radar,” he said.

At first Stambouli bought in bulk, broke up the lots and sold products individually, but found fewer hassles and lower labor costs in selling only wholesale lots.

Increasingly, Internet surplus sales are attracting individuals who want a home-based business to supplement their income.

Sean and Tina Sutherland of Huntington Beach, Calif., are buying Harley Davidson accessories and jewelry through Liquidation.com and eBay and selling through eBay and home parties.

“We looked at these wholesale prices and thought, ‘Oh my gosh, this could be a business,”‘ Tina explained.

Bulk buyers have to be careful from whom they buy, she adds.

Liquidation.com will accept defective merchandise back, but many surplus sellers won’t.

Caution has to go both ways, said Jack Glaser, who works for D.S.A.A., a Long Beach, Calif., online surplus wholesaler.

“We receive 50 to 100 e-mails a day from people who have merchandise they want to liquidate, but some are selling merchandise they don’t have,” he said. “Also, I’ve received fake cashiers’ checks from (foreign buyers). I didn’t ship the merchandise, but I know others who have, and they were ruined. The police can’t do anything.”