I think there are pretty good. There is definitely some resize distortion going on. What are you using to resize?. The white balance is perfect in all 3, not bad for a new dslr owner.
Compostion wise:
1.The car is really small in the picture, crop that down with either your lens/distance/crop tool. There is a light pole and tree growing out of your car.
2.Composition is much better (using thirds, good), again the light pole.
3. Excellent, these are one of my favorite things to do.
one of mine...

Keep at it! More pictures you take, the better you will get.