Those two majors are great for getting a job. If you are interested in government employment, I would recommend starting with the federal government job site, http://www.usajobs.gov
They have a Career Interest Center:
You can take an Interest Guide Questionnaire, or just specify which field(s) you're interested in and they'll show you a list of related government positions. Click on Career Interest Areas, then Leading-Influencing, then scroll through the list of job titles. You'll see many related to finance, such as Financial Analysis. You'll also see job titles like International Relations, if that interests you. This site lists job titles that you would find both in the federal government and in state governments.
Once you get an idea of some of the job titles, go back to the usajobs homepage to do searches for open positions. This way you can get an idea of what an actual job would be like.
You can also check out http://www.usa.gov,
the official website of the U.S. government. Click on the Jobs, Education & Volunteerism section:
Also, take a look at the site Making the Difference:
It's about working in public service (government) jobs, and it has good info about job types, internships, the federal student loan repayment program, and more. Right now under the Internships section, there is a posting for a financial auditor student intern in the Government Accountability Office. If you're a student, sounds like something you might be interested in!
Finally, if you don't want to work directly for the government, check out WetFeet's investment banking careers section:
Scroll down to the Career Tracks section - you might be interested in public finance.
I hope this helps answer your question. Good luck!