I've heard this question at least a kazillion times so i thought it might be nice to start a topic about it. On the internet you can find a really nice tutorial made by Toerti:
http://www.digital-experiment.de/Tutorials/NL-CarText-Tutor/English/TutorEng-Index.htm
If you still have any questions feel free to ask, maybe I or someone else can help you out. Have fun cartexturing [8D]
Greetz