Last time I was in Tokyo back in March, the Production I.G. Store wasn't around, so this was something I had to visit when I got back last September. From the Shibuya Station, the Marui mall is just up the road from the fork. Your landmark would the huge Adidas store. It's the building with the 10101 at the top.
It's mainly a merchandise store, so don't expect alot of attractions. Seeing the large Logicoma replica on display was already enough for me to oogle on. There was also a Ghost in the Shell VR experience on the side, but I didn't have the time to wait for the queue. Most stuff ranged from statues, to trinkets. If you're an avid fan (like myself), better watch out for your wallet or else you would be boring a hole on impulse-purchase stuff you won't need the following day. I kept my expenditures to a "minimum" to shirts, and patches (for my gi). If I didn't get a hold of myself, I would've spent on Tachicoma mints.
Production I.G. Store
Shibuya Marui 7th Floor
1-22-6 Jinnan, Shibuya-ku, Tokyo 150-0041
Business Hours: 11:00am - 9:00pm (8:30pm Sunday / Holidays)