Statistics/Information/All that jazz!

This is my first post, so if it is not in the correct place, my apologies.

My question/thoughts, I want to know all of the information I can on League gameplay. I know the spawn times of jungle monsters, I know that the caster minions are worth more. My question is, I see posts saying, "if you duo queue, you're placed against higher ranked enemies (mmr)." I just want information so I can play better. I know that I'm kind of just asking for anything you've got, but I really want to know, whatever there is. No bit of information is too small, I just don't know where to look. Links would help too!