Hi Joel
Start with this article:
Astrophotography with a Dob.
It's about 4 years old now, but it's still relevant. You can do very basic astrophotography with a dob, and your DLSR, but most of it will be of bright objects like the moon and maybe a bright planet - and it will likely all be afocal (pointing into the eyepiece).
A webcam might be an option for you, but is also more challenging.
Eventually you might like to get an EQ6 and mount your 8" tube on that. Then a whole new world opens up