Arduino ISP

Is there any way I can search for a specific variable (and it's content) before the Arduino sends it to the chip I want to program?

Which file exactly do you want to search ?
Unless it is the source code before being compiled it will have no variable names in it

Is your 'variable' something like a MAC address or serial number or encryption key where you want a different value in each upload without editing the source and re-compiling the sketch each time?