Hi Stephen - earlier in the year I was in exactly the same situation as you. I had a dob (200mm bintel f6 in this case) but was keen to get into imaging.
I too went with the NEQ6, and decided in the end to leave the dob as a visual scope and get a dedicated imaging scope - a GSO 200mm f4 imaging newtonian together with a Baader MPCC. Half the weight nearly of the 250mm, and a shorter focal length to make guiding easier. For guiding i'm using a LP 80mm f6 refractor and a QHY5 from Theo (gama electronics) as recommended by the friendly folks here on IIS. Also using a wide dovetail plate top and bottom, with the guide scope screwed directly to the top dovetail bar to maximise stiffness.
For the imaging camera - im using a second hand 400D which I have since modified to remove the internal UV/IR and anti-alias filters, and have fitted instead an Astronomik EOS-Clip L filter from Bintel. I run the camera tethered to the laptop, so the images download directly via the Backyard EOS software (about $20 i think). Finally i have a Bahtinov mask for focusing the whole setup, and am using the EQ6 direct cable so that I can control the mount from my laptop via the free EQMOD software.
I've also had a lot of fun recently using just a regular manual focus camera lens rather than through the telescope, so with the DSLR/scope/lens combo there's lot you can do.
Good luck,
Richard
