Hi Daniel
You can certainly motorise your existing dob effectively. Here are some resources that might help:
http://www.siderealtechnology.com
http://www.stellarcat.com/Pages/servocat.html
http://www.bbastrodesigns.com/StepperSystem.html
If you are interested in stepper motor systems then have a talk to Bojan who posts on this forum. He has made a Bartels system and worked with some other stepper based products.
I built a Bartels system which was a lot of fun. I later converted it to a sitech servo system which worked well too. This was for a home made 12 inch truss dob.
My preference these days is an Equatorial platform. I enjoy the simplicity of the platform and the fact it requires no modification of the dob mount. It raises the scope a few inches which can be an issue for taller instruments.
Hope that helps.
Rod