Ben - it is going to be a while before I get full use of my hand back, cleaning is going to have to wait!
RIC = Roman Imperial Coinage, the definitive guide. Comes in several volumes (VIII) is volume 8. Set of books is probably several hundreds of dollars. You can pick up DVDs on
ebay very cheaply, but they are hard to read at first, and you can't search the PDF files. My set cost £10. Search
ebay for RIC.
Wildwinds is a good starting place to look for your coins, but if you can't find it there, check out acsearch.com and coinproject.com. Check out the stickies at the top of the forum for really good reference sites and guides.
The way I cleaned my blank disk was to soak in DW for several weeks (it probably didn't need that long but I was ignoring it as it was so uninteresting). When it started to show detail, I used a scalpel blade to pick. You should use a toothpick at first till you get the hang of it.
Apply slight pressure to the "mud". You have to do it, making sure that the blade/pick does not go straight through the mud and mark the coin below. The idea is to just fracture the mud and then I use an unused blusher brush to get rid of the fragments. As soon as you find that you can't fracture any more of the mud, chuck it back into the DW for another couple of days and try again.
You will know when it is the time to move up from the toothpick to something more dangerous, but you will do less damage to the coin using a pick to begin with.
Different deposits will need different techniques, and lots of patience.