Do people with asperger's disorder usually suffer from motor-coordination skills problems?

Asperger's. Yes. Gross motor difficulties are common but not in all cases. Clay marzon, #1 surfer in the world is aspie. So it depends. Here is an overview. http://www.youtube.com/watch?v=xg1ngp1ngds.
Disorganization. Many children are disorganized. They can be clumsy, awkward, and have delayed speech and poor social skills. Labels are less important than providing therapy support to help them be normal. Most can learn very acceptable skills.
Sometimes. I don't know about the frequency, but i would say that a certain degree of clumsiness is not uncommon in kids with a variety of developmental disorders including autism spectrum disorders such as aspergers. Both fine & gross motor skills can be involved.