Well this brings back memories of my journey from dob to goto telescopes.
Most of the usual options have been covered of here but there is one that has been left out. Many people have retrofitted a Meade Autostar system to there Dob and various other mounts. This is commonly refered to as a "roboscope". There is a yahoo group called roboscope where people discuss such conversions.
http://tech.groups.yahoo.com/group/roboscope/
This is a good site with various conversions done.
http://bedair.org/ScopeStuff.html
I am actually using the Siderealtech Controller with Losmandy Servo motors on my G-11 mount. Dan Grays system is very robust and Dan actively participates with users why the yahoo group.
http://tech.groups.yahoo.com/group/sitechservo/
The Mel Bartel system can be built if you have the skill from ground up relatively cheaply. Mel also has yahoo group through which he interacts with the user base and is quiet responsive and very helpfull.
http://tech.groups.yahoo.com/group/scope-drive/
Another good resources for kits for either Mels Stepper system or Dan's Servo system is
http://gototelescopes.com
Gary's AN system while expensive comes with awesome support. And Garry is always available on the phone and willing to talk and help you with anything astronomy related. I have the AN and will be using it with my Siderealtech system to give me a portable system without the need for laptop.
Plenty of options out there. And also plenty of great people to meet along the journey, that perhaps is the best of all things.
Regards
Fahim