LucidSW - 4:52 pm on Jul 13, 2011 (gmt 0)
First of all, Google does not make recommendations of individuals or companies that provide account management services.
This Yellowbook obviously is trying to solicit more business but also trying to pass themselves off as Google. I'm sure Google would like to know about this so I'd report this business to them. They just happened to solicit to your clients.
Another thing, existing accounts of more than a couple of weeks cannot redeem vouchers. To me, that part is a lie.
Explain to your clients what's going on and not to contact them.
Being an Adwords Certified Individual or Company only means you've taken the tests. It does not give you special treatment, something else some are trying to convince potential clients of.