re: How do i get to the User made Maps on Portal 2?(Posted by sicboy on 12/29/12 at 9:07 am to Wooly)
When you click on the game, on the right on your steam desktop you'll see a "Steam Workshop" banner, and underneath it will be a "browse the workshop" button. You can browse by most popular today, this week, most recently created, or all time highest rated. There are also some for co-op that I believe will either say "co-op" or have a symbol beside it (not seeing one at the moment). When you start the game, go to "Community Test Chambers" and it will have your queue there.
Enjoy. Some of the better puzzles I've played have come from the workshop.