I enjoyed ‘The Dom’s Guide to Tickling’ by ERIK11. It’s got tons of ideas about technique — and it can be read by the dom or the sub, if you ask me! The author talks about various implements and restraints that can be used to enhance a scene, as well as some different ideas for tickling roleplay. He’s also got a section on how to throw a tickle party, too!
The book is for sale now on Amazon as a paperback or as an eBook.
The cover and back cover illustrations are by Achilles.
You can find the author on Recon under the screen name erik11.