I think the personals are a great reference tool and are a bit like a classified ad - post in that section exactly what/who you want and it serves as a reference, but I think the best chance of getting 'success' is by just joining in, chatting, adding/making friends, PMing people you think you might get on with with a nice message etc etc - most peoples profiles state their preferences just as well as a personals ad
even with personals, the chances are that anyone who sees your post will want to go through the process of getting to know you a bit anyway, so you may as well adopt all the other methods as well.
Even someone like myself, who is looking for some more tickle-meets, does not check the personal section that often, nor do I trust in the people that post their as much as those that I know from seeing posts elsewhere in the forum.
As a footnote, the most meaningful relationship I have formed through TMF was with someone who wasn't even into tickling, but had signed up in order to embrace her partner's fetish. I contacted her as I felt her post and profile matched the criteria I was looking for in terms of new tickle friends - it turned out she was not into tickling, or with the partner anymore, but we struck up a lasting friendship that I value to this day