The Economics Department has a tremendous record of placing students in top Ph.D. programs. Once there, former W&M undergrads have done quite well.
The majority of W&M alums with Economics Ph.D.s are teaching and doing research at leading universities. Some have held senior research positions in key government agencies such as the Treasury and the Federal Reserve Board. One has led the President’s Council of Economic Advisors. Our alums have also worked with international organizations like the World Bank. They have headed leading consulting firms. Several have taken research positions in prominent financial institutions.
General Advice for Graduate School
For current students planning to go to graduate school, or simply trying to determine whether a PhD in economics is right for them, we recommend a helpful website run by Sita Slavov, a former W&M student and current professor at George Mason University. We also recommend that any student who is ready to apply to graduate school consult the American Economic Association's website.
Recommended Undergraduate Courses
Most admissions committees will not care about the specific economics courses you have taken. They will care about your proficiency in mathematics. Most look for candidates who have taken at least MATH 111 and 112 (Calculus), 211 (Linear Algebra) and 212 (Multivariate Calculus). Moreover, one should have good grades in these courses. Here is some superb advice [pdf] from a William & Mary double major in mathematics and economics, who went on to do a PhD at Harvard.
That said, your undergraduate economics curriculum is not irrelevant. You will have an easier time at the graduate level if you have taken lots of econometrics as an undergraduate. Some 400-level economic theory would do you good as well. You will have a better idea what you want to concentrate on in graduate school if you have taken a range of economics courses at William & Mary.
For more information about planning for graduate school, talk to your major advisor.