The 52-year-old businessman had 21 new friends added on his Facebook profile today before two of them were removed only minutes later.

He only had only one friend listed on his page when he was reported missing on January 21 - a business associate from South Africa who told AAP she hadn't seen him in several years.

It's not known who is using Mr Rockefeller's Facebook page since his disappearance.

A police spokeswoman told AAP that no new information on their investigation will be released.

The social-networking activity comes after an unconfirmed sighting in rural Victoria and radio reports saying there was a second sighting of the Harvard graduate and property investor in Geelong.

Jan Spiteri, co-owner of the Gordon General Store northwest of Melbourne, says Mr Rockefeller came in on Monday morning and had a hot pie, sausage roll and a drink and returned on Monday afternoon to buy some milk.

"We still don't know 100 per cent if it's him, but we're pretty sure," she told AAP yesterday.

"He looked a little bit unshaven."

Gordon, a small township of less than 400 people, is close to where Mr Rockefeller's 2007 Toyota Prius was found undisturbed and locked near an abandoned country homestead on Monday.

Police say they are keeping "an open mind" in their investigation.