I'm about to do it and 2 instructors I know are Magnus Andersson who is VCDX56 so obviously DCD too. He's a VCI as well. Get him on twitter on @magander3. Magnus is mainland EU and you can get him on vcdx56.com
Paul mcSharry wrote the official VMware Press book I'm reading right now on DCD - he's UK based I think and is definitely DCD4/5 and a VCI as well. @pmcsharry and www.elasticsky.com
Hope this helps you !!!! And isn't there are scary amount of reading material !!!!!!!!!!!!!
Paul M