See below for a couple resources that have been invaluable for me in studying Korean and learning more about some of the history that has shaped this country.
Often forgotten in America and very misunderstood, it's clear when you arrive here that The Korean War has shaped modern day South Korea in many ways. I knew very little about The Korean War war prior to coming here but just after a few days I heard more references regarding Japan and North Korea from my students than I can count. Anyway, I'm not generally interested in reading about history but this book "The Korean War: A History" by Bruce Cumings is an amazing depiction of how things went down before and after the 38th Parallel was established roughly 70 years ago. I highly recommend spending some time to at least skim through this prior to coming to South Korea so you have an understanding of this important part of the country's history. Thanks to my lovely Aunt (Anne Joiner) for recommending this to me!
Korean Language Learning Resources:
By chance, the last guy who lived in my apartment happened to leave a Korean language learning book (unopened) buried in the back of the bookshelf when I arrived here. "Korean Made Easy for Beginners" by Seung-eun Oh is the book that I've spent most of my time in thus far and it's amazing how much this resource has helped me learn in such a short period of time.
Additionally, I purchased Rosetta Stone and have been doing it everyday. Thanks to a friend of mine, I've also recently started using www.talktomeinkorean.com as an additional resource. Of course, I also hang out with Korean people everyday and I'm not sure there's a better way to practice what you've learned than that!