Okay, so the solutions since FIFA 11 has become outdated were confusing for me and I had trouble. So I figured I will explain how I did it for those who were lost like myself.
1) Go to http://www.ea.com/soccer/fifa11
2) On the left sidebar there should be the option for "FIFA Creation Centre," click it.
3) There should be boxes with "Recently Crated Teams", "Recently Created Tournaments", and "Recently Created Players". Next to the "Recently Created Teams" tab on the right, there should be an option to click "More Teams".
4) Now there are going to be many teams, but they're all going to be from FIFA 12, so you need to click either "Most Downloaded Teams" or "Highest Rated Teams" and there should be plenty of FIFA 11 teams to choose from.
5) After picking one, Bookmark it, and then go to the Creation Centre in your game and download the team.
6) Go to a Kick Off game, and now there should be a spot for Creation Centre and the downloaded team will be there.
Hope this guide was thorough enough, but not too much to cause any confusion. If you need any help feel free to message me, even on XBL.
The Fifa website has been modified a little since the FIFA 13 release. My guide still works though, but the tabs you need to click may not be in the exact spot on the page as described. They are still in the same order though, and it shouldn't be a problem.