Do you have your ATP? If so, you can take the fast track and get it in no time. Under FAR Part 65.57 it says...

Experience or training requirements.

An applicant for an aircraft dispatcher certificate must present documentary evidence satisfactory to the Administrator that he or she has the experience prescribed in paragraph (a) of this section or has accomplished the training described in paragraph (b) of this section as follows:
(a) A total of at least 2 years experience in the 3 years before the date of application, in any one or in any combination of the following areas:
(1) In military aircraft operations as a --
(i) Pilot;
(ii) Flight navigator; or
(iii) Meteorologist.
(2) In aircraft operations conducted under part 121 of this chapter as --
(i) An assistant in dispatching air carrier aircraft, under the direct supervision of a dispatcher certificated under this subpart;
(ii) A pilot;
(iii) A flight engineer; or
(iv) A meteorologist.
(3) In aircraft operations as --
(i) An Air Traffic Controller; or
(ii) A Flight Service Specialist.
(4) In aircraft operations, performing other duties that the Administrator finds provide equivalent experience.
(b) A statement of graduation issued or revalidated in accordance with §65.70(b) of this part, showing that the person has successfully completed an approved aircraft dispatcher course.

If you have no experience, you have to do a minimum of 200 hours of course work. FAR 65.61

It looks like Lewis University offers a program in the Chicago area. Let me know if you need anymore information on being an ADX.