Just for the heck of it, lets try resetting your IP address.
First, lets get your current IP.
1. Get to a command prompt. (START, run, cmd).
2. Type: ipconfig
3. Write down what your current IP Address is.
Now lets try resetting it. This should work with most modems.
1. Still in the command window type: ipconfig /release
2. When that command finishes type: ipconfig /renew
Now repeat the first set of instructions and see if it is a different IP now. If it is, give the site a shot again.