In my experience Crucial have always got it right - in terms of sending the right module for the machine specified. Overnight delivery and a good returns policy.
You presume correctly - that ain't the place to be putting memory modules. Looks a bit like a mini-pci slot on the left but I'm not sure.
Without knowing the layout of your laptop it's not possible for me to say where you can find the SODIMM slot - have a nose around.