You would need to create the PS-ALI database from scratch, matching each extension with an emergency response location (ERL). You then upload that to the PSAP. Provide either PRI or CAMA trunks for 911. Caller dials 911, CLID gives the PSAP the location through a dip in the MSAG, and emergency services respond to the correct location.
The database is informix but I would not know how to interface with it the way you are talking.
The other person was talking about CER Cisco Emergency Responder. Your best bet would be to purchase this as it will interface for you and it is a pretty good system. Cisco came out with CER 2.0 which is also on a linux box.