I was wondering if anyone could tell me the best way to get from Eindhoven Airport to Geel by public transport
This is not easy, but possible. Take a bus to the train-station.
In Tilburg, take bus 450 (stops at the train station) to Turnhout station.
In Turnhout station, you can catch bus 490 to Geel.
Timetables busses: www.delijn.be
Of course, you can take a train in Eindhoven to Roosendaal, there change of train to Antwerpen and continue to Geel.