Entrepreneurship

One additional place to look for possible supplier partnerships is through the trade associations. 

There are several ways you can look for these:

Go to IBISWorld, and 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. 

In addition, try Googling for your industry name and "trade association". That will find some of varying sizes, although they might be buried in page 2, 3, or more of the results.