Starting Point for New Soccer Fan?

As a member of many sports sub-reddits, I have been on the other side of this kind of post a million times, and I am sure I am faaaar from the first to post one of these here. Nevertheless, I am going to try my luck. I am an American who has been drawn into soccer by my father and some friends who discuss the easy to find TV showings of the international competitions. I don't need a run-down of the rules or strategy or anything, I have all of that quite down/down enough. I am looking to learn about the leagues, the teams, the competition, etc. etc. I have for reasons I only semi understand been drawn to everything Irish in soccer, so I'm thinking of looking into the Irish League, although I'm sure there isn't nearly as much to say as they don't get talked about like La Liga or Barclay's or Serie A. I don't know, I suppose I'm asking how I go from being a casual fan to knowing enough and getting involved enough to see through a whole season in a league? Maybe I'm talking non-sense or something. If anyone bothers to answer anyway with some suggestions or links or something, it would be much appreciated!