Clowns, especially false and true percs will host in just about anything, a anemone is not even needed. And, as the others stated, clownfish take to specific anemones in the wild.
With that said, I don't recommend recreating an anemone/clown relationship because anemones currently have such a poor record of survival in captivity. Also, most clowns these days have never even seen one as most have been tank-raised. I have personally seen tomato, false, and true perculas take to a wide range of pseudo-host including mushrooms, Zoanthids, Sarcophyton, and various LPS
corals (most notably Euphyllia sp.). My own pair of perculas has taken to a hammer coral (E. paradivisa):
If you would really like to study up on clownfish, and potential true and pseudo-hosts....I recommend Joyce Wilkerson's Clownfishes
book as an incredible resource from captive care to breeding. It also details specific anemone/anemonefish relationships for those who feel they may be ready and able to try the real thing (if so, E. quadricolor does seem the "best" option right now, and a natural host for several species of clowns)
--Sorry for the longwinded first post, I am getting deep into clownfish and potential breeding right now so a lot of information is fresh in my head