At https://www.dmachoice.org you can opt out of receiving catalogs, magazines and other mail offers. This is a free service offered by the Direct Marketing Association. Once you opt out it can take a few months before you see a change in the offers.
As well as stopping killing trees due to the amount wasted paper this service also dramatically reduces the credit card offers. Criminals often look out for these types of offers and steal them from mailboxes, sign up and watch out for paperwork so they can perform identity or other types of theft.