Where in the bible will I find this?

it's actually, "Your word is a lamp unto my feet, and a light unto my path" Psalm 119:105

You will find atheism by reading the bible

May I recommend www.biblegateway.com? They have a wonderful search engine for finding scriptures. For instance, if you choose the New International Version bible from their list and type “lantern feet” in the search box, you won't find anything. But if you play around a little bit with some synonyms and instead type "lamp feet", two scriptures pop up including Ps 119:105 which is obviously the one you are looking for.

If you’d prefer to download your own free bible search engines, you can do so at the websites below. (Each has their advantages and disadvantages compared to BibleGateway.)

http://biblesoftwarefree.com/

http://www.e-sword.net/index.html