In this case you just want to access the data register itself.
PORTB and PORTD registers contain the pin data you are looking for. I finally got access to an Arduino to figure it out. You want to use bitRead(PORTD, pin)
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Serial.println(bitRead(PORTD,3)); //Reads bit 3 of register PORTD which contains the current state (high/low) of pin 3.
Reference Bit Read Operation for more information.