Please try contacting several custom/portable sawmill operators on the following directory created by the Illinois Urban Wood Utilization Team:
http://www.illinoisurbanwood.org/documents/ILCustomSawmillsDirectory2011.pdf
However, most of these custom/portable sawmill operators are not in the business of removing yard trees, nor are many custom sawmill operators and traditional loggers willing to assume the extremely high cost, risk, and liability associated with removing individual trees in residential areas, not to mention the specialized equipment needed in many situations. This is exactly why the vast majority of residential tree removal projects are a net "cost" project, not a net "profit" project to the homeowner.
Of course, you can always try contacting a licensed timber buyer via the following Website if you truly believe your trees to be of legitimate and outstanding commercial value for lumber or veneer:
http://dnr.state.il.us/law3/timber/09/TBlist.pdf
Best of luck!