Hello Ryan,
The best advice I could offer would be to develop a business plan for your idea. Since there are so many potential applications for GIS services in the realm of Ag and Transportation I really can't be more specific than that. Once you have an idea of what your professional GIS service or forte is, you cant then do some research about your potential target customers. It could be transportation related to grain or fresh fruit and vegetables or it might be GIS services related to laying out a corn maze for an agritourism business. This will help you to determine how to position your business, give the customer base you might target or attract.
For assistance in developing a business plan or doing other research, I would strongly suggest that you contact your nearest University of IL Community and Economic Development Educator. A listing of that team can be found at http://web.extension.illinois.edu/state/staff.cfm?ExtTeamID=4
You can also find assisstance and support through the Small Business Development Centers. Those offices will be found most likely at a local community college but will be listed in the phone directory as the Small Business Development Center (SBDC)
I Hope this helps. FYI, I am no longer working for U of I Extension but still get these messages as I am still with the University. I'll be glad to follow up with referals if you have additional questions, however, the local extension contact found at the web link I provided will have better information specific to your location.
Best of Luck. John Pike
