Welcome to 17th Shard!
Just saying, if you haven't read about 50% + of Brandon's cosmere books, then get reading quickly. Otherwise, you might not understand most of our topics. Stormlight Archives (an ongoing series) is a good series to pick up after Warbreaker.
Here's a few links that will help you with your Cosmere and realmatic Theory. Don't read it until you have finished Mistborn, since it contains spoilers:
http://coppermind.net/wiki/Realmatic_Theory
http://coppermind.net/wiki/Shard
Here is a list of abbreviated book titles you will find useful, listed chronologically:
From the Stormlight Archives:
WoK = Way of Kings
WoR = Words of Radiance
From Mistborn:
tFE = the Final Empire
WoA = Well of Ascension
HoA = Hero of Ages
AoL = Alloy of Law
From Warbreaker:
Warbreaker = WbFrom the Books set in Sel:
Elantris = Elantris
Legion and the Emperor's soul = (not sure, it's also only a short novella)
From the Alcatraz series (a series of children books, but still good)
There's no abbreviations I've found, sadlyLook out for an awesome character called Hoid or Wit. He appears in nearly every Brandon Sanderson Book, like a cameo, although sometimes not.
Best wishes and may the Storm bless you!