Unsafe site found

Where is the place to report this?  I found an unsafe site, upon visiting which brings up an extra browser window offering to deliver a driver checker or driver downloads.  I will quote the site address; and some monitor or administrator should do what must be best:

http:/ /www . mathwarehouse . com /arithmetic/numbers/prime-number/prime-factorization . php?number=173&primeFunctions=Find+the+Prime+Factorization

and the same address in a broken form which I am breaking here intentionally,

http:// www . mathwarehouse . com /arithmetic/num  bers/prime-number/prime-factorization.php?number=173&primeFunctions=Find+the+Prime+Factorization

Something about Norton is not catching this, either the Tool Bar, or the Norton product  (N360).  Firefox and Google Chrome.