There is an easy way to discover which keywords your competitor is
This service called swerush.co.cc allows you to type your competitorís
url and itíll find the keywords they are purchasing on AdWords.
The way it works is that they have a crawler and a large database of
keywords and they just query Google for all those keywords.
So the first difference will be that youíll not know what your
competitors are actually buying, but rather for which search queries
they are showing (which actually is more important anyway).
To use it for AdWords you use your competitors URL followed by ď(by
Click here to try it: http://www.swerush.co.cc