The sheriff's office said that investigators, acting on an anonymous tip, searched Patrick Ange Molesti's house last week.
He was not home at the time, but investigators said they seized his computer where they found evidence of child pornography, the sheriff's office said.
No other information has been released regarding the alleged attempt to buy the child.
The sheriff's office said Molesti is believed to still be in the metro Atlanta area.
Authorities said Molesti, a French national, is 6-foot-1 and 200 pounds. He has brown hair and brown eyes. He is possibly driving a 2002 white Chevrolet van and likely armed with a handgun, police said.
Anyone with any information about Molesti's whereabouts is urged to call Cherokee 911 or detectives at 770-928-0239.