When I go to look for my demo, I got to My Computer, Local Disk, then I click on program files but cant find steam..HELP ME!!

it could just be in your local disk that is where mine was for a while

or you need to look a little harder try sorting the folders in your program files by name then hitting "s" and look for it there

does your computer have more than one local disk?

you can also try searching your computer for "steam" and it will show you where your folder is

ok thanks, and I only have one local disk!

Then shouldn't be harder to search for "steam" and your files will be there.