not free but maybe useful
I haven't used them, but they are a listed vendor on the Catersource site.
Caterers Web Help
Another thought is to join one of the lead generator groups like localcatering.com or directcatering.com (there are others but these are the two I have found most useful) YOu prepay an amount of $40 or so and then can buy leads that interest you. There is a whole art and science to responding to leads in order to get the business and alot of times you get no where but I have generated alot of business this way from small jobs under 1k to large jobs of over 40k. Considering you are paying $3 a lead - think of it as a starbucks that gives you some bang for your email@example.com.CaterersWebHelp.com
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