I have auditioned for a CESD agent in my acting school about a year ago and they seemed like an excellent agency. I want to submit again but I don't know how or what to give them??
Their site does not give a specific address for submissions, and the only thing that seemed really vital other than a headshot/resume was a tape IF I was submitting to the voice over department.
I have their address, but is there a certain department I can specify or anything I should include?

I would find out which agent attended the audition at your school, and address the submission directly to them. Include a headshot, resume and a cover letter. In the cover letter, be sure to mention the school audition, and let them know your future plans (for example, do you plan to move to NY or LA?) After your submission, keep in touch with them via postcard when you have something important to report, and if you don't hear from them, submit again in 6-8 months and repeat the cycle until the time is right!

Best of luck to you!