LibreX - Framework and javascript free privacy respecting meta search engine
AnyMailFinder.com - Find anyone's email address
Searx - Open source metasearch engine
Atomic Email Hunter - Atomic Email Hunter is an incredibly robust tool that specializes in extracting email addresses, along with usernames, from various webpages.
SearXNG - SearXNG is a free internet metasearch engine which aggregates results from various search services and databases. Users are neither tracked nor profiled.
Scrape - Gather all website emails in seconds