Going to do business on the Web? You'll want to get yourself a great domain name, which might not be as easy as you think. Some entrepreneurs run into trouble when they discover that someone else has beaten them to the name-registering punch. Others have problems keeping their URLs when someone challenges their right to use a particular name. This sort of wrangle seems to plague companies both big and small ? those with venture funding as well as those run out of home offices. Here are four variations on the theme:

Company: Salon.com
Concept: Smarty-pants San Francisco-based Webzine
Revenues: $2.9 million
Dot conflict: Founder David Talbot loved the domain name Salon.com, but so did a man in Texas who wanted to start a portal for hair salons.
Resolution: For nearly six months, Talbot had to content himself with a clunky alternative, Salon1999.com, before moving the site to SalonMagazine.com, where it resided for two years. Before the company's initial public offering, Talbot's vice president, Andrew Ross, negotiated the purchase of the coveted address for an undisclosed sum. Ross's challenger moved his portal site to Salon.net. Talbot's company now owns the trademark to Salon.com and Salon.

Company: HotJobs.com
Concept: New York City­ based job-search site
Revenues: $3.5 million
Dot conflict: When the company went to trademark the HotJobs name, it found that two other companies ? including one direct competitor ? had already applied for it. Right before HotJobs.com went public, the gossipy industry trade Silicon Alley Reporter mentioned the dot-com's oversight in an alarming mailing-list column that called the trademark conflict "potentially disastrous."
Resolution: "The Office of Patents and Trademarks has declared the terms 'Hot Jobs' too generic to be trademarked by anyone," a spokesman for the search site reports. HotJobs.com's August 10 IPO floundered, closing at less than its offering price on the first day of trading. But the company's stock has been trending upward steadily since then.

Company: Hireminds.com
Concept: New York City­ based job-search site for journalists
Revenues: Unknown
Dot conflict: "I didn't realize ? stupidly ? that I had to apply for a trademark for the name also," says founder Laurel Touby. "I figured, 'Hey, I'm using the name. I'm safe and set.' " But then a challenger from Cambridge, Mass., applied for the trademark for "Hireminds .com." He also registered such variations as Hire-minds.com, Hireminds.net, and Hiremind.com. "He called me and tried to buy my domain name from me, telling me he basically had all associated names," Touby says.
Resolution: None yet. Touby doesn't want to sell but may change her mind. She would like to avoid costly litigation.

Company: Eve.com
Concept: Start-up women's beauty and cosmetics retailer based in San Francisco
Revenues: Unknown
Dot conflict: The URL was owned by Evangeline Rogers, a six year old girl in Virginia. The situation forced company founders Mariam Naficy and Varsha Rao to try reaching an accord with a kindergartner. Rogers's parents mediated negotiations with the retailer but left the final decision in their daughter's hands.
Resolution: The partners consulted baby-naming books and conducted a study. Eve tested better than any other name. So they tried again, but the young girl balked. Idealab, the company's financier, encouraged Naficy and Rao to persevere. Eventually, they made the girl an offer she couldn't refuse. The ultimate price tag: a family trip to Disneyland; a Compaq desktop PC; $500 worth of merchandise from Idealab-backed eToys Inc.; an honorary seat on the board for six months; and an undisclosed sum of cash. "Looking back, it's probably one of the best investments we've made," Naficy says.

Of all the above scenarios, the HotJobs.com and Hireminds.com cases are the most typical. Unfortunately, they're also the kind that is usually the most costly, according to Lynn Tellefsen, marketing director of MicroPatent LLC, a clearinghouse of trademark information based in Connecticut. "Many people don't recognize that there's a policy in place that says that federally registered trademark owners are protected against infringers of domain names," she says.

"Please warn others to purchase their trademark along with their domain name to save themselves a lot of aggravation later," agrees Hireminds.com's Touby. The bottom line: search one of the on-line databases of trademarks to make sure no one has a prior claim to your URL. (One popular such site can be found at www.uspto.gov.) Then file for a trademark as soon as you come up with the domain name you want. An added bonus: trademarks can be used as collateral in gaining a bank loan or a line of credit. (The mark's value is usually equal to your revenues.) But more important, the real value of a trademark is peace of mind. "It's not fun talking to people who have this problem," Tellefsen says. "There's really nothing they can do."