I am not sure where you are located. My recommendation for substation engineering courses if you are in the U.S. would be Sargent & Lundy. They have a week long course which I have attended and found to be excellent. The course is taught at their offices in Chicago and taught by people from within the organization. Their expertise is evident in the quality of the material and depth at which it is the course is taught. It covers a lot of information and actually gets into some depth unlike some other courses I have seen which are just a lot of fluff. The classes are typically taught twice a year. You can check on their website
You may also want to check out Shaw PTI as well. They have an extensive list of course offerings in addition to offering a course in substation design. Their website is
Engineers where I work have recently (November 2004) attended the Substation Design courses available from the University of Wisconsin (held in Madison and in Las Vegas). I have been told the course, altough only a few days, is fairly extensive in that it covers foundations, grounding, structures, arrangements (Ring Bus, Breaker-and-one-half, etc.) protective relaying, etc.