I know there have been other threads on this topic but I decided to just start a new one. This is interesting information that I just found: (forgive me if someone else has posted this already!)
http://www.spdfoundation.net/gifted.html

I had previously commented that my investigations couldn't find any correlation with gifted and SPD, but seems I might be wrong (imagine that, my DH says!) At my new job, with so many new kids to see, I'm finding a VERY high number of kids with dyspraxia and modulation disorders who are also quite gifted!! Made me start looking around some more. I still wonder though whether some of it doesn't just constitute differences and not a disorder. Goes back to how you define disorder, I suppose.

I also got this link off another board:
www.itsyourhealthradio.org
The host is doing a whole series on SPD with interviews that are downloadable from the site. Click on "Past Shows" to get the audio from already aired shows. They are airing in May.