PA-23 pilot used a GPS to navigate to an airport but programed to the VOR of the same name. When ATC questioned heading the pilot detected the error and became reoriented.

Narrative

Departed for GSH. After takeoff I contacted SBN Approach and asked for VFR radar service. SBN Approach advised me I had an IFR flight plan waiting; so I decided the IFR clearance to GSH which was 'cleared as filed' (I filed direct GSH VORTAC direct GSH. I was going to go VFR but I observed light snow ahead). SBN Approach called and asked me to let him know when I had the airport in sight. When I got 5 NM from the airport; I clicked the mike to turn on the runway lights and saw nothing and no city lights. As I passed over what I thought was the airport below (ground is snow covered) with no lights; SBN Approach called and asked if I was going to GSH since I was heading southeast over the GSH VORTAC. I instantly turned to a 080 degree heading and saw GSH 8 miles east. I answered SBN Approach and confirmed I was going to GSH and that I had the airport in sight. SBN Approach cleared me for the visual approach and I canceled my IFR 3 to 4 miles west of GSH and continued VFR to the airport and landed. What were the factors in this event? 1) I was running late. Hurried departure. 2) I set GSH in the GPS but didn't notice the GPS was set for VOR. I set GSH VOR in the GPS instead of GSH airport. I focused on the GPS instead of taking the clues from the heading/VOR indicators and outside reference. 3) I didn't pay attention to the course on the ground even when my heading to GSH airport and ground referenced didn't look right. 4) First time I had flown this aircraft in about 2 months. Very little recent time in this aircraft. 5) Didn't use the autopilot to fly the aircraft as I was checking things out. What actions would have prevented this event? 1) Slow down and double check everything especially since I had not flown this aircraft in almost two months. 2) Take note of the setting on the GPS (airport; VOR; NDB; and intersection). Don't focus on one thing; scan! Be aware! 3) Take not of clues from all sources (visual; VOR; heading). 4) Refresh memory on avionics that are different. 5) Use the autopilot to fly aircraft when there is a need to check things out.