I don't know that there is a list. There may be somewhere. Generally if you make that mistake, your post will be unceremoniously yanked with the message, "we don't want stuff from that site here." You're not likely to make that mistake again, well, unless you're like a few folks around here who like to live dangerously and provoke the mods out of some sense of indignation. Hint: the mods ALWAYS win at that game.