onemoreshow

Hi, I'm new to Rock band using a PS2 & am un-clear about were to go to download these DLC's???? I am assuming, witch I hate to do, that DLC stands for new stuff(Songs) released for this game??? I am really interested in what is avialable for this game & what web site sells addictional stuff??? I read Harmonix but don't see anywhere to buy, all I am finding related to this is forums. Can anyone help me out??? Thanks, Cunfused Rock Band Rocky