So after examining close-up pictures of "fennel pollen" (at least, the retail stuff like this:
http://www.pollenranch.com/fennel-pollen-spice.html &
http://www.igourmet.com/shoppe/prodview.aspx?cat=Salt+Spices+and+Extracts&subcat=Spices&prod=4339&name=Fennel+Pollen&cf=usp_ListProducts_Sel&cprod= ), I've decided that it is actually the fennel
flowers. Of course, the flowers are tiny, yellow and fuzzy-looking, so it's an understandable misnomer. It's also something of a relief, because I went a-foraging a few days ago to a patch of wild fennel. I harvested around 50 smallish 'heads' of flowers, then left them to dry overnight on a big paper bag, as suggested on this website:
http://fleaabouttown.blogspot.com.au/2011/07/free-fennel-pollen.html.
Next day, I examined the yield - it was ridiculous, about enough to cover my fingernail! Then, on closer examination, it didn't even seem to be pollen. Now admittedly, I don't have a microscope or even a magnifying glass, but my eyesight is pretty good, and this tiny pile of yellow looked more like tiny little fennel-flower petals to me. So, with that decided, I went about detaching the rest of the flowers. Many came off just by rubbing them between my fingers, and I ended up attacking some of the more stubborn heads with nail scissors. The yield was about 2 tablespoons.
I may go back and have another go using the "fresh harvest" method, and see if that yields any more actual pollen.
But in the meantime, I have my (no doubt pollen-rich) fennel flower-buds. They're lovely. Very sweet, and a strong, lingering fennel-oil flavour, with none of the "grassiness" of fennel bulb/leaf, and none of the woodiness of fennel seeds (though as others have said good-quality, freshly-ground seed would be the nearest substitute). I plan to use some on my next chevre.
Also, if anyone in Australia is unable to source this ingredient - well, first I would suggest looking in the nearest open space beside a railway track, as they grow feral along every rail line within a few hundred km of Sydney, and also along roads. Be quick though, as the wild fennel will start to go to seed soon. And if you still can't find any and have some cheese project that requires it, PM me your address and I'll post you a spoonful. According to other forum members, a teaspoon is enough for ~500g of chevre, and you would use even less for any kind of aged cheese, so that should go a long way. Only while stocks last!