Axes are rare outside of China...
...but not at all uncommon inside China.
I published Black Whirlwind Axes: The Legend of Li Kwei way back in our Outlaws of the Marsh special (2002 July/August). It was more of an overview of th Li Kwei legend and its connection to axe forms.
Our forum sponsor MartialArtsMart actually sells two pairs of axes: The wushu pair, which is hollow, and the Dragon Well pair, which are freakin' wrist breakers. I'd love to see someone manage a form with the Dragon Well pair. Neither are great sellers in America just because axes aren't commonly practiced out here. That's too bad really, since the axe has a lot of history. And there's nothing like a good battle axe. MartialArtsMart also carries a long stick axe (also a hollow wushu version). This is very rarely practiced, but often seen in weapon racks guarding temples.