Dan,
Here is a good general eel article...
http://www.reefkeeping.com/issues/2002-12/fm/
Otherwise, here is what we know....
The biggest thing about them is that they are "escape artists" meaning you need to seal up every small opening in your tank or they will get out!
They all have eaten fresh frozen octopus very very very well! Brian tries to give some to the new eel owners to start them off. This will take a little prep work on your end to buy fresh octopus, chop it up, and then freeze it. Some people use feeding sticks to make sure the octopus gets to eel without other fish snagging it.
Also, very small slow fish (such as a tiger goby) may be at risk of becoming dinner.
The scientific name is gymnothorax melatremus which may aid in your research.