Greetings Mike:
Well, I don't think you are going to have much luck finding someone to buy your ponderosa pine yard tree simply because (1) it is a pine and not a black walnut (2) few people in Illinois mill conifer species.
You can always try contacting local buyers and portable sawmill owners from the Illinois Sawmill Directory, but I don't think you are going to have much success.
http://dnr.state.il.us/conservation/forestry/05/sawmills2005.pdf
Several other options include local newspaper advertisements; local woodworker shops; Internet (www.woodweb.com; www.woodfinder.com); etc.
More than likely, you are going to have to pay someone (certified arborist) to remove this tree - if indeed you want/need to take it down.
