When it comes to fantasy football, Mike Persson knows how to use the Internet to make things happen.

He had been casually surfing the Web when he learned that the Denver Broncos had named Mike Bell, an undrafted rookie running back from the University of Arizona, as the starter for an upcoming preseason game. Persson immediately logged into his fantasy league on Yahoo and tried to pick the rookie player for his team.

But Yahoo didn't know about this guy yet, at least until Persson shot off an e-mail to the support desk. By the next day, Bell was on Yahoo's lineup of available players, but as luck and timing would have it, someone else had already taken the running back.

Fantasy football leagues, for the uninitiated, are made up of imaginary teams that are created by fans who pick players and earn points based on their real-life performance on the field.

The concept of fantasy sports has been around for decades, with amateur league commissioners using charts and newspaper statistics to manage the points — and bragging rights — for the different teams and their "managers."

But with the growth of the Internet, fantasy football has evolved from a recreational activity to a big business. Today, according to the Fantasy Sports Trade Association, which represents more than 100 member companies, 15 million to 18 million people participate in fantasy sports leagues.

When it comes to player statistics, look no further than the Internet. Need an update on a score or a play? Those can be accessed through your cell phone. Need to call a league meeting or get a message to the other managers in your league? That's what online chats, message boards and e-mail are for.

There are Web sites that help manage fantasy leagues. Some come from companies we might expect to be involved: Yahoo, ESPN, CBS Sports. Others have catchy names that might appeal to the sports fans: The Huddle, Head2head and Footballguys, among them.

Some of the Web sites offering fantasy leagues charge for their services; others give them away in exchange for the traffic that you will drive to their site. (Be prepared for the advertising blitz.)

Persson, who has used Yahoo for free fantasy sports gaming for years, is happy with the support he gets from the Web company, even though he realizes that there are plenty of advanced, pay sites that will offer more features and services for the hard-core fantasy players.

For $25 for a team or $125 for a league, players on Yahoo's Fantasy Football Plus package get access to live online chats, league communication tools such as message boards and access to the league's progress from the player's cell phone. Paying customers can also customize point total and league rules to meet the needs of their players. Prizes such as T-shirts and trophies are available for the league winners.

NFL.com, which also offers free fantasy football, has a $130 Field Pass option that delivers up-to-the-minute statistics and live play-by-play audio broadcasts for games outside your area. Interested in a souped-up experience but unwilling to cough up $130? Consider the NFL's $3.99-per-month Fantasy Companion, which allows you to use your cell phone to get updated scores or change your player lineup while on the go.

Persson, who has enjoyed playing for free for years, likes what the pay sites offer, but isn't sure he's willing to shell out cash for something he enjoys for free now.

"I may upgrade to a pay league next year, but I've had a great experience with Yahoo's free site over the last few years for football and other sports," he said.