Hi /u/TheDarkLordOfViacom - thanks for reaching out.

There are a few secondary resources that I'd recommend for someone looking for an introduction to Shi'ism, but the number one is is Heinz Halm's Shi'ism, but if you are interested in the origins of Shi'ism, I would also recommend having a look at Maria Massi Dakake's The Charismatic Community: Shi'ite Identity in Early Islam, which looks specifically at the so-called "proto-Shi'a" or the Alids and how the theology developed.

I hope this is helpful.