Here is how we usually proceed:
1. Collect product requirements (from the client)
2. Run a quick market study to evaluate the time we will have to spend
3. Provide a quotation for the first service, and get approval from the client
4. Identify a list of suppliers from various sources
5. Provide a report in Excel with information collected and full contact details.
When working with us to identify new suppliers, this is basically the process we follow for you.