IBISWorld Search for your industry (or the supply industry to yours -- e.g. if you are making ice cream, your supply industry is the dairy industry). On the first page of the report, scroll down about halfway to the Additional Resources section. Many of these resources may be trade associations. Check their Members page, or look at their annual conference directories -- often suppliers or other support industries (e.g. refrigeration, storage, transport, etc.) will be primary vendors/supporters of their conferences.
