There are many online platforms and databases that can help you find and research potential investors for your startup. Some examples are Crunchbase, AngelList, PitchBook, and CB Insights. These platforms allow you to filter and search by industry, location, stage, sector, and other criteria. You can also access information about the investors' portfolio, track record, preferences, and contact details. You can use these platforms to create a long list of potential investors and then do further research on each one.