Joanna, I'm not sure if there is a formal page on the website giving information on that, unless
this link is it (under Responsibility of Contributors). I think it's just been said before by the admins that new members can't post blogs or include links for a few days (not sure on the exact time).
Hope this helps.
ETA: Actually, I'm not even sure if new members aren't allowed to post links. I think they can, it's just that if they're a spammer, they'll get banned.