A coworker showed me something they downloaded called Process Explorer which appeared to show all processes running on a pc and the locations from which they ran. From this you can probably determine what directores/files might be executing this driver detective that is pestering you.
In addition to deleting files and directories you might also search your registry for entries that might relate to the software and get rid of them.
You might also consider running system restore and pick a restore point from prior to the date you first installed the driver detective.
I downloaded the free version of Driver Detective thinking I was downloading something else. Then I tried to uninstall it and thought I had succeeded. But it continued to attempt to start up when I logged on to my computer profile but this time I got an error message. So I searched my computer and deleted every file and folder with Driver Detective in the name. After a few hours it had reinstalled itself. So I tried to uninstall it again but a file was missing so I couldn't uninstall it. It continued to try to start up whenever I logged on and then gave an error. It also tried to start up several times each session on the computer, and crashes my browser when it does. So once again I searched for everything with Driver Detective in the name on my computer and deleted it. To no avail. I have tried the search and delete again but doubt it worked. It's like having a virus!