Why Can't I see my website when I put localhost in the url

[new_mamp_user]

I just purchased a new Macbook and downloaded MAMP. I have MAMP installed in my application folder and everything seems to be installed just fine. It has given me the password and user, I can see all my php info, etc. I am new to this so I am doing tutorials on working with dynamic websites. Part of my tutorial is me downloading the tutorial files from http://sawmac.com/dwcs5/. We are working on this site cosmo_shop. The instructions tells my to place the file in my htdocs folder. It says once I do that I should be able to type in http://localhost/cosmo_shop/ and I should be able to see the website, but I can not. Nothing comes up, the screen is just blank. My tutorial book says if this happens my sever must not have been set up correctly...Does anyone have any suggestions as to what I may be doing wrong? Please help....

[kleinweby]

If you're really meaning MAMP and not MAMPP/XAMPP then you are in the wrong forum and you should contact the support of MAMP.