kshaund:
The problem arose when I went to upload my sketch.avrdude reported an invalid signature for the 328p sig = 0x1e9406, after googling for answers I found out this is the id for a 168.
Were you using ArduinoISP to try to load the sketch? Does your Duemilanove have an ATmega168 in it? If so, you forgot to disable auto-reset and you're talking to the Arduino bootloader on the Duemilanove rather than the ArduinoISP sketch. They both speak variants of the STK500v1 protocol.
Disable auto-reset by connecting a small capacitor (1-10 microfarad) from the Reset pin of the Duemilanove to the Ground pin. (The + side of the capacitor goes to Reset and the - side to Ground.)