When writing my last blog
Your Inner Consultant: Reading the signs. What can you learn about an organisation from its car park.
I realised that the smoking areas outside factories would be a great place to find people who want to stop smoking. You can find industrial estates and factories almost anywhere where there is a reasonable population. Sometimes they are on the outskirts near the megastores but in some places e.g. Birmingham they are pretty much in the city centre.

This is what I would do. Search google for with the words "trading" "business""industrial" and "estate" together with the name of the area. When you find some places bring them up on google maps and select satellite view. You will then get an idea of the size and layout. Parking spaces generally mean people so you can get an idea of potential customers.

Visit the area during a smoke break, lunchtime is easiest as people will have more time. Unless it is a defence or aerospace site you are unlikely to have to go through a security barrier. If you are confident chatting to people then just go up to them and ask if they would like to to save some money by stopping smoking. You could just leave cards and leaflets by the smoking area but I think talking to people will be far more effective. If you are very good then you might even persuade the HR people to let you use a room on the site for a few hours.

Not tried any of this myself but I frequently see lots of smokers outside the factories I visit and some of them must be ready to stop. Hope this helps.

I've had a friend of mine that is a hypnotherapist have great success with this tactic but he targets pubs and clubs. He had the great idea of making a lighter with his name and phone number on it. He gives the lighter too them and has a little script which goes along the lines of "Everytime you use this lighter think about how your life could be better if you weren't to smoke, and if you find yourself feeling it is time to make a change, call me now"