Be glad they didnt go at it with a flat head screw driver and break the tumblers in the door lock or the ignition. Major pain in the ass to fix if the car is even there in the morning. Im kind of suprise they didnt try and take your car. Consider yourself lucky bro. But really thee is no way to truely stop a car thief if they want your stuff bad enough
Example: Cousin had a 2001 SI and had spent a little over 600$ dollars on a touch sensative car alarm and getting it installed and everything. It parks right in front of his bedroom window every night and about a year after it got installed he came out to go to work and his entire car alrm system had been pulled out of the car and laid in the parking spot and his car was gone.
All you can really do is slow them down. I suggest making a killswitch for now till you can get a car alarm. I have lost a few hondas to car thiefs. With my G1 I am going to shave the door locks, have a basic car alarm, and dual switch fused killswitch.