Lee's list is very comprehensive, and so i would consider my answer an addition to his.
Speaking as a Sephardi Ba'al Teshuva myself, i have found a few things out that are rather annoying.
That most Sephardic things are not translated into English, and it doesn't look like that will be changing anytime soon. And even the things that are translated into English are often translated by Ashkenazim. The Guide to Serving God by Abraham ben haRaMbaM was most recently translated by an Ashkenazi scholar, so you will see things like "Shabbos." The same thing with the new translations of Chovoth haLevavoth
That many of the talks about Sephardim come from an Ashkenazic perspective, or are given by Ashkenazified Sephardim. You ask an Ashkenazi Rabbi why Sephardim do things differently and a pretty common response will be "they didn't have modern technology where they came from, or they weren't trained in science, and so they mistakingly do what they do."
So for your library i would start with a few books that would get you familiar with the development of Sephardi halakha, so you can understand where a lot of the differences stem from.
A good English book on this is:
Rabbinic Creativity in the Modern Middle East by Zvi Zohar
http://www.amazon.com/Rabbinic-Creativity-Modern-Middle-Library/dp/1441133291
This book is ideal since details the gamut of Sephardim in their native countries, how they made halakhic rulings, and their philosopical outlooks.
And since you are interested in Sephardi halakhic rulings, there is a new book series in development called
Mishnah Berurah Tiferet
You can read about it here: http://yeranenyaakov.blogspot.com/2014/02/mishnah-berurah-tiferet.html
My last recommendation is a book series called the Keter Shem Tob by dayyan Shemtob Gaguine, which is a compendium of all the Sephardic customs spanning the entire Middle East and the Western Sephardic communities of London and Amsterdam. This series doesn't get a lot of attention but is truly a great addition for any Sephardic Library. You can find more information about it here: http://www.ketershemtob.com/