Welcome! Now that you have located the HOSTS file, you must ensure whether it's working or not!
Open your fav. Browser and type in the address :testingmyhostsfile.com. If Google site opens up, you can be sure it's working. Updating the HOSTS file is another kettle of fish altogether.
I will suggest a program ,SPYWAREBLASTER, which is equally effective. Download site:SpywareBlaster® Download
Now here's abit about Spywareblaster: Works for Internet Explorer, Firefox and most Web browsers. It uses a list of adware/spyware sites very similar to the one in the MVPS HOSTS file but without messing with the HOSTS file or the DNS Client service. There are 13 350 items in SpywareBlaster's database!
SpywareBlaster will even create an encrypted backup of your HOSTS file with its Hosts Safe option.
SpywareBlaster works by entering a list of adware/spyware sites to your browser's Restricted Zone and Blocked Cookie list. Updates have to be performed manually, weekly, for the free version of SpywareBlaster. Been using the program for years without a glitch. Highly recommended.