Is what you have located relevant and reliable? Are you uncertain whether to use the information you have found? You can use the CRAAP test to evaluate the information you find.

Currency: 

How current does the information need to be? Do you need to use information published in the last five years or are older, seminal works fine to use?
 

Relevance: 

Does the information found answer your question? Do you understand the content and is it at the right level for your purpose?

Authority: 

What are the author's qualifications? Are they linked to a particular organisation such as a university, research institute or government department?

Accuracy: 

Is evidence given for the research undertaken? Can you verify the information presented by using other sources? Is there a bibliography or references given?

Purpose: 

Is it trying to communicate research, persuade you or sell you something? It is expressing an opinion, or is it balanced and objective?