Just got my OBi100 setup, and I did two things to test the Anveo E911-only service (in Santa Clara, CA):
1) called 933, listened to the info repeated back, made sure it was accurate
2) called the SCPD non-emergency dispatch number from their web site and said "I have a new internet phone setup at my house and need to verify it can call 911 correctly. What's the correct procedure?" The dispatcher basically said "just call 911 and say right away that it's a non-emergency test call". Hung up, called 911 and got the same dispatcher. She verified that my correct address showed up. The callback number she had wasn't one I recognized, but I believe Anveo generates those on the fly.
Hmm, as an aside: if you ONLY have E911 through Anveo, how does it route a callback to your OBi (in my case, my SP1 is Google Voice).