For all anyone knows, Benjamin Stribling had never been to Longview, Wash. He didn’t know anyone here and would probably have been hard pressed to find Cowlitz County on a map. But in March of last year the 26-year-old Colorado man used his computer to reach out more than 1,000 miles to commit a sex crime in West Longview, where his victim lives.

Stribling, who was convicted last week of trying to convince an 11-year-old girl to e-mail him naked photos of herself, presented a unique set of problems for the prosecutor’s office. Prosecutors had to extradite Stribling from Colorado Springs. They had to prove he was the man behind the screen name “Loving Passionate Guy,” from which the e-mails originated. And they had to fly nine witnesses from Colorado and California.

The case illustrates how the Internet has broken down geographic barriers for law enforcement and may force local detectives and prosecutors to reach far beyond their own jurisdictions in the future. It also shows how investigators are having to adopt new methods for tracking down those who commit crimes on the Web.

The Stribling trial was the first of its kind in Cowlitz County, prosecutor Sue Baur said. “It’s going to happen more and more,” she said, as law enforcement gets better at investigating such crimes and more people report them.

Cowlitz County Sheriff’s Office spokesman Charlie Rosenzweig downplayed the unique nature of the case, saying local investigators have analyzed the contents of computer hard drives and chased down the people behind screen names in the past. But, he said, the Stribling investigation and other Web crimes have made it necessary for the sheriff’s office’s four detectives to learn new methods for analyzing large amounts of data that could be introduced as evidence.

“Now we’re seeing cases where you may have tens of thousands of images that have to be analyzed and located,” Rosenzweig said. “It’s not uncommon for a kid to send more than 10,000 text messages a month.”

Cowlitz County authorities learned about “Loving Passionate Guy” after the Longview girl’s mother, who had been monitoring her daughter’s Web use, contacted the sheriff’s office. A detective used records at Yahoo! Inc. to connect the screen name to Internet Protocol addresses (the unique codes that computers register when they connect to the Web). From there, investigators traced the IP addresses to Stribling’s parents’ home in Elbert, Colo.

During last week’s trial, the prosecutor’s office brought executives from Qwest Communications in Denver and Yahoo! in San Jose, Calif., to illustrate the investigative method. Prosecutors also flew in detectives, probation officers and even Stribling’s parents from Colorado. The cost for the witnesses’ airfare, car rental, food and lodging: $7,500, Baur said.

At a time when someone can commit a crime in Cowlitz County from across the world, how far will the prosecutor’s office go to convict them?

Baur said she wouldn’t rule out asking federal authorities to track down a suspected Web predator in another country. Still, she said she wouldn’t always pursue an out-of-state suspect as aggressively as she did in the Stribling case. The prosecutor’s office, she said, doesn’t have the staff or the money.

“We have to set some priorities,” she said. “I can’t say prospectively where the line is.”

The Stribling case “screamed for a conviction,” Baur said, largely because of the defendant’s history of sex crimes and the age of the victim.

Stribling, was convicted of incest in 1998 and of sexual abuse in 2003, after he groped and touched a woman in a car. He was convicted in 2005 of extortion after he hacked into a woman’s e-mail account, discovered erotic photos of her and threatened to post them on the Web if she didn’t have sex with him.

Stribling, who is scheduled to be sentenced next month, also sent provocative “questionnaires” to girls, Baur said, and kept a list of those who had answered questions to his satisfaction. Evidence indicates he was exchanging messages with at least 20 girls when he was arrested, she said.

“I think he’s extremely dangerous,” Baur said. “He’s progressing in his acts. He won’t stop.”

Stribling is also charged in Colorado for sending the lurid e-mails to the Longview girl, but Baur said she didn’t want to leave it to Colorado authorities to convict him.

“I can’t rely on the fact that they will get them,” she said. “I know I will.”

John Shehan of the National Center for Missing and Exploited Children, said his organization gets an average of 100 reports of people stalking children on the Web each week. The number, he said, is going up, partly because more people are bothering to report occurrences.

But Shehan, the director of the center’s Exploited Child Division, said kids are connecting to the Web in ways their parents can’t always monitor. More and more kids carry inexpensive, Web-enabled cell phones, which means they can send and receive private messages across dozens of Web sites from school or their bedrooms. And video game consoles like the Xbox and PlayStation now connect to the Web and allow gamers to compete and chat across the Web.

“These types of cases, they don’t know boundaries,” he said.