User Submitted Content Copyrights

[Crashmaxx]

I am making a fun website that has Chuck Norris like facts, but with the Stig from Top Gear instead. I am having users submit their own facts with a very simple form, and I will later add the good ones to the random facts that pop-up. I'm not quite ready yet, but you can look at it and give me feedback if you like:
http://www.tamedracingdriver.com

Anyway, I want all the content that isn't a quote from Top Gear to be under the Creative Commons Share-Share Alike license or similar. But under that, there is suppose to be attribution to the creator and I currently have nothing to record or display a name. Plus, I'm not sure I can have them automatically put under this license, but I think I can as many sites seem to have submitted content become their content.

So how should I manage this? Can I just say that it will all be attributed to my site or myself? Or maybe anonymous? Or can anyone help me with some php to have a name associated with each line? Currently each submission just gets written as a new line in a file and I will later manually move all good lines to another file that displays them. Is this a terrible way to do this?

Thoughts? Questions? Comments?