Just walk past the shops. Most of the time it is easy to see what they sell and you can ask them for a particular item or brand. Buying local usually involves legwork and talking with people. I hope it helped. However I really find it hard to understand why being able to buy legos locally seems that special to you (when I was growing up I only knew of local shops and I still prefer them).
Now this is giving me splinter cell vibes. I hope the CIA is not missing any agents in the area.