The Mining Journal - trade magazine - was created in 1835.

Trade Publication

Basically they are the same in their application - to generate sales.

The difference is one advert is aimed at people who are in a specific trade and the product is something that non trade people would not use. i.e. specialised equipment.

Landing magazine is a trade magazine for real estate agents, builders and brokers, it was first published at Kansas city in Missouri. It has a digital edition that could be find online.

I believe there is a trade magazine called "Call Center Magazine." Perhaps that is a good place to start.