I've been a male lee for a long time. With the exception of a few dry spells here and there, I've had little to no difficulty finding willing female lers. The key to success is not to play it up as a fetish, but more of a fun thing to do. If a woman likes you, and knows you like being tickled, it'll happen.
Unfortunately some guys are desperate for tickling, and women smell that desperation a mile away. To those guys, I would advise shelving your desire no matter how strong it is. Get to know a girl first. Find one that likes you, and then SLOWLY introduce the idea over time.