For those who are interested in an accessible entryway to the world of Kabbalah, my translation of the classic Kabbalistic lexicon Gates of Light is available on Amazon. Rabbi Yosef Ben Avraham Gikatilla is now considered to be instrumental in the popularization of the Zohar along with Moshe DeLeon.

You can read a part of the introduction at KabbalahonLine.org. Just click on these links and they will take you there.