Just one required reading for this topic, but it’s fairly long/involved. It’s the Wikipedia entry for Economic Systems. What I like about this reading is that it really helps bring out the variety and complexity of economic “systems”. It really is much, much more complex than the simple “capitalism vs. communism vs. socialism” that we are often taught in K-12 schools or that are used in popular political discourse.
I suggest doing two things here. First, explore. Don’t just read the text, follow some of the links in the article to gain a richer understanding. Second, it’s worthwhile to remember this article. It will make a useful starting point for some additional research for when you start writing longer posts on your blog or when you write about the book project.