Wobble, or Death Wobble as it's sometimes called, could come from several sources, generally all of which originate in your front suspension and steering components. This would include any or all of your four tires. A tie rod even slightly bent from an off road trip or hitting a pot hole can be the culprit as well as worn bushings at the sway bar or other components. Another source of wobble can be the result of even a minor suspension lift including the use of larger tires than recommended by the manufacturer.
I highly recommend that you take this to a professional shop that can measure and adjust your front end because if left as it is, well, they don't call it Death Wobble for nothing.