[ubuntu] noob help required Duplicates

Hi, I am new to ubuntu. I found an old laptop in the cupboard and dusted it down to try out the operating system. I am hearing loads of great thing about it. But it just doesnt seem to work. I installed version 12.04 LTS but anytime I try to install anything by fallowing instructions to the tee I still get errors mainly this one.

W: Duplicate sources.list entry http://dl.google.com/linux/chrome/deb/ stable/main amd64 Packages (/var/lib/apt/lists/dl.google.com_linux_chrome_deb_dists_stable_main_b inary-amd64_Packages)
W: Duplicate sources.list entry http://dl.google.com/linux/chrome/deb/ stable/main i386 Packages (/var/lib/apt/lists/dl.google.com_linux_chrome_deb_dists_stable_main_b inary-i386_Packages)
W: You may want to run apt-get update to correct these problems

and each time I do as it says, (run apt get update) but it just continues to give me this error.

Any help would be appreciated. Thanks