For those in the know it might be worth looking around the street and back a block or so on the west side of the Saphan Khwai BTS station on Saturdays and Sundays. Lots of amulets and little statues there.

The Military Junta has been busy closing down street markets, rousting long-term residents/squatters, establishing Special Economic Zones and generally reshaping Bangkok, and the country, to be "green" ( as in Army, not eco-freindly ). I think they shuttered the famous Tha Prachan Amulet Market ~ 1 year ago.

"Authorities said they suggested the Tha Prachan amulet vendors move to alternate, distant locations, such as one on Rama II Road or the Bang Bua Thong market – an hour drive away on the outskirts of town."

That said, there are markets in every neighborhood (still), and many specialty markets. You can't swing a dead soi dog without hitting at least two markets here.