I am located in Brazil and after reading much about iSwifter, decided to try it. But nowhere in the app store can I find it. I have followed links from sites and tried every kind of search in the app store itself but it always comes back negative. So I was wondering if app store content is restricted depending on my location.*

Yes, apps are location dependent. Even though many apps are distributed worldwide, are there always some that are only sold in certain countries, often for legal reasons.