To force your computer to point at a specific IP address when resolving an address, use the steps below.
1: Open up notepad on your computer as administrator. (Otherwise you can't save your changes)
2: Open up the file C:\Windows\System32\drivers\etc\Hosts
3: Add a line to the bottom in the form of "IP Address" "URL"
4: Save the file
Now your computer will go to whatever IP address you are pointing it at. If you want to connect to the old site, either delete the line or put a # at the start.