Perhaps I could be of help.
My personal favorites are....
The Yenny Series: The title character "Yenny" has very large feet that get into the craziest of tickle situations. Possibly the most popular example of foot tickling in art form, almost every comic in the series pays attention to this specific interest as well as other places. I totally recommend this to you and every other foot tickling art fans.
http://www.mtjpub.com/mtj02_publications.php?series=58
Nesse series: Another large footed character that is as tough as she is ticklish is Nesse from the "Nesse" comic series. Artist Jai Sin makes sure to focus heavily on her big feet within very dramatic tickle scenarios that don't feel out of place with the overall story.
http://www.mtjpub.com/mtj02_publications.php?series=4
The Yoly series: Made by "The Oz, creator of the Yenny series, this spin off of the Yenny tickling series pays attention to Yenny's Hillbilly cousin. This series presents more extreme tickling situations and story than the more random Yenny series, however there is no shortage of foot action. The Oz has mentioned that each of the antagonist in the series have varying tickling styles which add plenty for everyone. There is also a sub comic with one of the series' antagonist's called "Anabelle" which though short, provides much foot tickling and is worth a look. Yoly's popularity is rapidly growing and might even surpass Yenny's worldwide fame some day, that is if the Yenny series is ever put back in motion.
http://www.mtjpub.com/mtj02_publications.php?series=60
The "Tats McCree" series: Made by veteran artist Tomato Dragon, Tats McCree is a clumsy and unorthodox cop who manages to capture thieves with a grand amount of luck. Her feet are a heavy target for the bad guys to access. Comic number 5, being a personal favorite, provides an exceptional desperation tickling scenario with Tat's hanging on to a window ledge with just her feet. The loose drawing style and cartoony action make this series a wonderful purchase like the other comics I've mentioned.
http://www.mtjpub.com/mtj02_publications.php?series=6
The "Vellicatrices Unlimited" series: Possibly the series with the most attention to feet I've ever seen, this series is a wonderful blend of tickle action and story. Full of wonderfully drawn ladies and intricate situations, his series promises not to disappoint.
http://www.mtjpub.com/mtj02_publications.php?series=41
These are just a few of my favorites that have to deal heavily with foot tickling. Everything provided by MTJ publishing is possibly some of the best and most diverse assortment of tickling artwork and literature available. Just browse the publications from time to time and you might find something that you like. Also if you can, go to MTJ pub's deviant art page. They provide very good descriptions of all publications they have.
Here is their page.
http://mtjpub.deviantart.com/
I hope all this helps! :d
