Warren,
Welcome to the area. Where are you from and what kind of riding are you used to? Smithville is your closest single track option and the trails there are very well kept and get lots of riders. They do a weekly night ride.
Check out more info on that ride at:
http://forums.earthriders.com/viewtopic.php?f=2&t=13226Just scroll down to the latest page and info. The Earthriders web page is also a good source to get information about area riding and meet some great trail people. I'd suggest joining the group.
We have a 7.5 mile linear trail at Indian Creek Community Lake, which is about 10 miles northwest of Chillicothe. It is a pretty epic ride if you go up and back starting at the Campground Loop on the east side of the dam. You can drive Hwy 13 through Hamilton and drive backroads to Poosey Conservation area.
We also have some pretty awesome trails at Crowder State Park, which is a couple of miles out of Trenton.
That is the stuff close to you. There are lots of riding opportunities in the KC area. We have a very strong trail building/maintaining group. Come on up and ride with us some time and we will get you pointed in the right direction. There is plenty of gravel in your area. including that gravel road that pops out of Polo and goes east all the way to Bunch Hollow and the area south of Chillicothe. Lots of hills. There is a gravel ride that start and ends in Lathrop every year in July. This year it was just short of 100 miles. We do a gravel grinder out of Jamesport every year on the 1st weekend in February called Chuckies Challenge.
That should be enough info to get you stated!