Graduate school in economics
Information from the American Economic Association on preparing for graduate school
This is a very helpful website with a lot of useful information on economics programs, math preparation for PhD programs, program rankings, careers in economics, etc.
Williams College Economics advice on preparing for PhD program in economics
This page has a lot of good information, and a number of helpful links to other relevant sites.
Advice from Susan Athey (Stanford) on graduate school in economics
Advice from UC Berkeley Economics on courses to take in preparation for an economics PhD
Extensive and detailed advice from Richard Startz, UC Santa Barbara