TopCoder used to be a great place for this. After every 'match' there were write-ups and discussion on how to solve the problem in different ways etc. I learned

TopCoder used to be a great place for this. After every 'match' there were write-ups and discussion on how to solve the problem in different ways etc. I learned a ton from there ! Also, as other said - there is no easy way around it - it's hard work (but still fun) and you have to take the hard road - working on the problem until you solve it (or your pre-defined time runs out) then reflecting on what was good / bad in your thinking process.