A1 sells several different models of alarm, keyless entry, and door lock systems. Without seeing the installation diagram for your unit it would be hard to give any recommendations...
If your talking about the starter kill feature you'd normally install a new relay inline with the vehicles starter relay control wire coming from the ignition switch under the dash. There are several ways this relay can be wired depending on the alarm systems input/output. Same goes for the horn control whether or not its a ground or power output at the alarm module.
Can you post a copy of the installation instructions?
2001 Ranger Edge 3.0 V6, 5 speed M/T
Limited Slip Differential, James Duff Traction Bars
Kumho 30x9.50 15 MT / Black 297 Series 15x7 Rims