I think that means he had a hearing today for his arrest on Tuesday, not some prior charges.
Regarding the evidence, the articles don't specifically state that he was found with articles belonging to Samantha, or even evidence that he kidnapped Samantha, per se.
The way I'm putting it together, before his arrest, LE in AK considered him a POI and had reason to believe he (or his car) was in Texas because Mankiewicz said they had been working with Texas LE for "several days". Then out of the blue, a police officer in Lufkin, TX, stopped him on a traffic violation, ran a make on his license plate, and discovered the out of state bulletin. They searched the car and "found enough evidence in the vehicle to arrest the driver for suspected kidnapping..."
http://www.alaskadispatch.com/article/suspect-arrested-samantha-koenig-abduction-case
If there were already grounds to suspect him, say he used her credit card, or LE verified a tip, and LE found a roll of duct tape for instance, or a length of rope in his car, or other items commonly used in kidnappings, I'm fairly certain that would suffice as evidence
to arrest him on suspicion of kidnapping. It seems that so far he's only been charged with device access fraud. JMO
Read more here:
http://www.adn.com/2012/03/15/23730...isappearance.html#storylink=cpy#storylink=cpy