Been there, done that and even acquired several T-shirts during a successful 7 year career (1988-1995) in leading publishing houses with internationally known titles. It was enormous fun, immensely educational and hugely rewarding.
If you'd like some constructive advice on advertising sales? Ask my brain! (Just don't ask it to sell any more advertising. A brain can have too much of a good thing.)
Products - to trade
My brain has sold perennial plants from a Dutch exporter to nurseries and mail order companies in the UK (1999-2005).
Products - to members of the public
Delving back into the archives, somewhere back in the early 1980s my brain got up on its feet and knocked on doors to sell items as diverse as book club membership to cosmetics. Yes, my brain was a Avon Lady.
It's also worked in clothing stores. And on market stalls. And behind several bars in pubs and clubs.
Ice to Eskimos
Nah, just joking. Though I'm sure there's a business opportunity somewhere.