I can't seem to find an answer for this anywhere.
An icon before the label on the default tabcontrol tabs would suffice for my needs.
Thanks in advance.
Q: You need to clarify what library set you're using: Winforms, WPF, ASP.Net, GTK#, etc. – Nathan Ernst
A: You are totally right, my mistake. I'm using Winforms. I switched back from WPF, since WPF was crashing in some computers.
It is a built-in feature of the TabControl. Drop an ImageList on the form and fill it with your icons. Set the TabControl.ImageList property. For each tab page, set the ImageIndex property.
Drag and drop an imageList from the toolbox on the winform and add images to collection from property window. Add a tabcontrol and Set the TabControl.ImageList property. Set the ImageIndex property for each tab page. see example http://www.youtube.com/watch?v=D7E6xJyd6KM