Thanks muchly for that link, dstar. I didn't know about that site. It doesn't sound, though, like some (if not most) of the hairs work very well in the game, and Cazy's abandoned the effort, as she states in a sidebar:
"some hairs are experimental don't share to many peoples (forums, etc.) / (some hairs may not upload for some reasons: scale, through face, flaws, etc. there are many hairs not passed, sorry for any problems on the hairs i cannot fix it or too tired
there are many things makes me don't want to do any conversions one are most of them are failed), i'm off to try something on another games, thank you for visiting."
So I'm going to try some in the game but I'll try not to be too disappointed if they don't work, or don't work on particular Sims.
We're all still learning.
Turns out the one I liked (the red, in the elf ears pic) is a converted Peggy donation hair (ick), but it looks pretty good on the elf
so I'll give it a whirl.