Just searching around on Google the other night I turned up a fan fiction from a Daria website, about Quinn getting buried in the sand and her feet tickled by Sandi, Stacy and Tiffany. Considering it's not a tickling story by definition (at least I don't think it's intended to be) it contains an awful lot of tickling action. Enjoy.
http://www.outpost-daria.com/fanfic/payback_is_a_beach.html
http://www.outpost-daria.com/fanfic/payback_is_a_beach.html