Dear Ryan,
This is Matan from GammonEmpire.
Offline promotion can be used to create branding or as a direct marketing tool. Obviously, the latter is relevant to you.
From my experience, offline direct marketing is more expensive, slower but creates a much better player value than online.
If you’re planning to target specific individuals, CD’s + sign-up coupon codes are the right approach. If you plan to make a more massive “non-targeted” marketing, expect a maximum conversion of 5% from CD’s to depositors for the most targeted audiences. For example, when I attended backgammon tournaments in Vegas we handed out GammonEmpire CD’s and got precisely 7 depositors from 150 cd’s handed out. Whether it’s worth it or not, is up to you. I think that in the case of mass marketing, CD’s are a good choice for brand owners only and will not produce positive ROI for affiliates.
However, I do remember an interesting case of a guy called Nick, who distributed CD’s on his rich Beverly Hills neighbourhood and got stunning conversoin and player value. Out of 25 depositors he made more than $50k. 
So, when it comes to offline, I think you should stick to the coupons (they are trackers, on top of being deposit-incentives) or personally hand out cd’s, and choose carefully who you’re giving them to.
-Matan.