Across the country, investigators are stalking Internet predators, from those who lure children they meet online into a sexual relationship, to those who assault toddlers and post images of their crimes.

Authorities are making strides, but investigators and organizations that work with them say the task forces are underfunded and vastly outnumbered. They've identified more than half a million U.S. computers that have traded child porn.

They're getting some help, though. A handful of states have pitched in funding. That includes Virginia, where the legislature approved $1.5 million for the state's two Internet child-crime task forces. The Southern Virginia Internet Crimes Against Children task force will use its $750,000 to double its staff of three investigators.

The U.S. Justice Department created the task force program in 1998 to support state and local law enforcement. Task force investigations led to more than 2,400 arrests in fiscal 2007.

While some states provide additional funding, many task forces rely solely on about $250,000 in annual federal grants. They say it's just not enough.