There are many great search engines that can help you find open positions when publicized. Here are a few that are specifically focused on international development and non-profit sectors:

• Devex.com
• Encore.org
• Idealist.org
• Indeed.com
• Nonprofit-jobs.org
• The Bridgespan Group
• Commongood Careers
• The NonProfit Times
• The Chronicle of Philanthropy
• International Organization Careers