How do I receive magazines and posters from Sony Playstation?

How do I receive magazines and such from Sony Playstation. I heard there were promotional codes on Sony things. Also I mean receiving it by mail. So anybody who has a good answer receives 20 points.|||I joined the Playstation Underground and then once I bought a PS3 I linked my underground with my PSN account and I periodically receive offers etc from Sony. Go to playstation.com and sign up !|||ok this is what I did. I went to walmart and went to were the magazines were and found the playstation magazine and just took out the subscription form out of it instead of buying the whole magazine and just sent it through the mail and got my magazines