Hello Paul, and welcome aboard! 8)
I'll give you a quick answer, as I'm sure others will elaborate more on this topic...

- Philips Webcams, like the Toucam Pro or the Vestas, are great for planetary imaging, but not for DSO imaging unless heavily modified.
- DSLRs are wonderful, and VERY WIDE FIELD due to their enormous chip. But they are NOT as sensitive as dedicated CCD cameras, unless modified. (Hutech does this modification, and also the Canon 20Da was modified with Astronomy in mind)
- Dedicated CCD cameras are great, but as you already noticed, their price range goes from $250 to $12000 or more... 8O
Remember that the objects that you are imaging are very far, and very small, in comparison to "NORMAL LIFE" stuff, so that's why you can get by with a CCD that is so small... (of course, if you want wide fields, and your wallet can handle it, WHY would you settle for that?) 8)
In order to take advantage of the wonderful "imaging scopes" out there, and the wide fields that some provide, you "should" get a camera that handle it, and that's why you'll see those MEGABUCKS cameras out there (besides other things, like extra sensitivity, low noise, water cooling, etc, etc)
Clear skies! 8)