I've called 911 because I had no other number and have said "This not an emergency, transfer me to a non-emergency line". That way your call is clear of the incoming emergency trunk lines.

If anyone cares, most cell phones you cannot disconnect automatically from 911, you have to press a combination of keys to disconnect. On landline phones, the 911 operator "seizes the trunk", and you cannot be disconnected, unless the 911 operator releases the line. There may be similar technology on cell phones today, but onces the handset stops transmitting... well, you can't have a connection anymore!

Also, Phase 2 wireless is available in a large number of jurisdictions, and they may be able to locate your phone. Unless something is heard, I don't believe most are investigated due to the amount of false alarms and man power to search for a needle in a haystack.