Welcome, Sascha! Good luck with your diet resolve and new habits. Your doctor has probably already given you good medical advice because you are pre-diabetic. Fitday has some good tools to help you stay on track following that advice (I'm thinking of the food journal, for example).
If you have specific goals, it's easy to measure your progress with the tools available here. And as far as motivation, we all need that! I wish they could put that in a bottle and sell it.