real absinthe is... unique... smelling, and different places use different herb combos and thus the smells vary widely. There's a strong anise/licorice smell from both aniseed and star anise, but it's more complex than that. Most of the absinthe knockoffs in the US just load up on the anise and ignore lots of the other more interesting ingredients, so at that point you might as well be drinking Ouzo.
In general, well made absinthe will also carry a noticable fennel scent, wormwood itself has a bitter & menthol-y smell that is very strong in more powerful absinthes, and the other herbs like hyssop that go in usually lend a cut grass, almost vetiver-ish note to the thing. Especially in some Czech absinthes there's a strong citrus note.
About the closest scent to traditional absinthe you can grab on the US market today is Chartreuse, or the less common Herbsaint, although both have some different herbs and not smells as "bitter" as the real deal . You can always brew up some homemade absinthe, of course, but that can smell *profoundly* vile =)
Uh... not that I know anything about that..... uhm.... yeah.
(I actually really like Fou d'Absinthe, btw.)