1) lighting is always a good deterrent. both inside & out. invest in a small home automation kit
2) make sure there is no space for a person to hide behind your bushes.
3) alarms are good but only if you use them correctly -have them tied to the lights.
4) add some burglar proof locks to the doors/windows. techno-mall.com
http://www.youtube.com/watch?v=nNwXk1qp_CM
