When evaluating a particular source, ask yourself the following questions.
Is it Authoritative?
What credentials, or ethos, does the author have?
Is the author cited by other sources?
Can you find info on the author?
Is it Objective?
Is there a sponsor?
Is the author trying to sell you on something?
Does there appear to be any bias?
Are opposing views addressed?
Is it Up to Date?
When was the information published/updated?
Are the links current?
Does the subject of your research necessarily need to be up to date?
Is it Accurate?
Has the source been peer reviewed?
Are there any mechanical errors (grammar, punctuation, spelling etc.)?
Does the author concur with generally held notions of experts in the field?
Is it On Topic?
Will the reader be able to connect the info to the topic of research?
Is this source necessary to further your thesis?