Ironically I just did a podcast interview with a board development expert today. Podcast will publish mid-December.
So, this is a two part question. If you are just starting your NP and need people to help incorporate the organization, then get whoever you can (friends, relatives, co-workers). This way you can get all the paperwork started.
Once you are up and running you will need skilled board members. You can go to Professional Chapters (like Bar Association, Chamber of Commerce, Unions, Corporate HR departments) and ask them to help you spread the word. Leave official paperwork, brochure or some type of documentation outlining your organization and your needs.
But if you are only just starting – then get people who are willing to have their names on the incorporation papers. The incorporation process can take time and your board development is a long term process.
Hope this helps.
Nonprofit Ally Founder/Admin