If your friend is picking up computer hardware make him meet you are Narita. He can take the Keisei Limited Express or the JR Sobu Line pretty cheap. Or if your friend has a car, have him park and pick you up. The airport has conventional short term parking just like a US airport.

I'd be more concerned about getting the stink eye from the customs people. In the US at least I've seen customs shake people down bringing in non-laptops.