As others have said, oud smells vary a lot, depending on the quality, variety, and how it's used (oil or smoked)-and in the same way, western oud reconstructions vary a lot depending on the model. Our Arabian BNers can elaborate on this.
Oud is combination of woody notes (including wet, rotting wood), animalic dirty notes (some Indian ouds are at times described as fecal), strangely mineralic notes, and sweety fruity (not in the smoked form), or smoky leathery (in smoked form) ones. Sometimes the combination comes across as having a distinct band-aid note, as others said.
Try to smell your way around. Tom Ford Oud wood touches on most of these notes and gives some ideas, even if it is not necessarily the most distinctive one. Dior leather oud is a good example of smoked oud.