You can seek to enforce it in Oregon (the state which issued the order). You should not expect to recover travel costs or legal fees, although you may be able to recover your legal fees. (Expecting to recover them is usually met with disappointment.) You can consult an Oregon lawyer to see what they would charge to initiate proceedings. You can also check to see if your local prosecutor's office has a support enforcement office, as you may be able to get them to initiate collection proceedings.