Tony was a technologically gifted inhabitant of Nipton, killed in the Nipton Massacre in 2281.
Tony has been responsible for fixing up a terminal for Major Steyn as well as a number of other technological feats, e.g. fixing and activating two Mister Gutsy robots.
Despite his skill, the rest of the town considered him a freak of some kind, though it's not explained in what way. In his diary, Tony mentions impressing an out-of-town girl with a robot so that she stays with him before the rest of the town can turn her against him. He also mentions that in case he succeeds, it'd be a nice change from having to pay Rosie for sex.
Tinker is mentioned only in Fallout: New Vegas.