I need a list of websites that my isp deny

[undercoverdaememon]

Hi everyone, let me explain:

Mi ISP's internet proxy it's a ISA Server 2004 or 2006,
They deny sites from categories that they don't give me to me,
( I have an ISA 2004 behind them ), I think they use surf control
like I do because it's corporative stuff you know.

My big problem comes from the fact that some time ago I got a denied page and that page says that it will be notified to the admins, etc. For the purposes of your understanding I'm an admin too, but I'm not connected directly to internet but trought them. I need to know where are these sites and if exists such a online tool or something else that give to me this websites or categories of websites for surfcontrol, thanks in advance.