When I sign up with a new company, I always broaden the search esp in the Sassie platform to look at the whole US that gives me an idea what clients that MS works with so just in case that client decides to expand to my area, I can keep an eye out. However, I see Chris Ruth with a particular MS but I have yet to see it in my area and I have 2 of them near me, I'm thinking either those two are not shopped or they are given to long time shoppers of that MS. Now, I monitor that MS board more than some others.
Also like Prince said above, I sometimes google like just today I googled Jamba Juice + MS ( after seeing another post here) and a very old post on babycenter came up, with the MS that does Jamba Juice, they have since changed names and I'm signed up with that MS but have never seen Jamba Juice, so either they are with a different MS or I just miss the timing...
Like everyone else says sign up with as many as you can!
Good luck!