I'll pay you to help me secure my home

I recently learned about Arduino while searching for a way to make a device that will add an additional layer of security to my home. I've determined that I don't have the time to learn how to do this myself, so I'm looking for someone that I can pay to do it for me. Here's what I'd like done.

I would like to have a device that uses a motion sensor to detect when someone is outside my front door. When motion is detected, I want it to trigger a random series of audio files on an mp3 player that is connected to an amplifier with speakers. The audio files would be those of a large ferocious dog growling, barking and a combination of both.

I know that there are products out there that do this already, but I want something that sounds more realistic. I can purchase/provide any necessary hardware, I just need someone to program and set it all up. Or if you already have an old Arduino laying around that could work, perhaps I can buy it from you and you can get an upgrade?

My email address is in my profile, or you can PM me. Let the bidding begin!

I think it'll sound like a recording of a dog still.
Why not go with an audible announcement, "Intruder Alert, Notifying Central", some 'Clicks', followed by some DTMFs?
Evidently, Parallax's microwave motion sensor can work from behind doors.
There's Sparkfun's MP3 player and the Adafruit Waveshield (it's a kit).