The guidelines that would help you in negotiating for salary during the interview process are here:

Before the interview, know what you want and prioritize what's most important to you in your new job-money, more responsibility, work/life balance, a shorter commute, corporate culture-before you begin interviewing. Be prepared, you should be ready to convince the recruiter that you are worth the amount at the higher end of the salary range. The easiest way to do this is to provide very specific examples of how you can add value to this organization-just like you've done throughout your entire career.