I visited a company last week, who had taken out the whole back page of the Thompson. One year on and they were extremely disappointed, "knout" (Lancashire I think, loads of green stuff and weird fat sheep type thingy’s everywhere) :-/
YP use a lot of standard formats and graphics throughout the book, so if you are not absolutely specific, they will use what’s easy and cheap.
People often rely on these books as a sole source of work, and for some trades that’s ok, but it seems unless you have a large add in the same place for years, you are more then likely gonna be disappointed. Although a lot can influence the results like placing, wording, dodgy company names and even the type of address you use.
On the other side of this, I continue to have a number of people say that they got us from the yellow pages, yet I have never advertised my current company there ever.