Email Extractor Software for Mac?

[Biggs101]

I have been using emailextractorPro for the past few years to locate emails relating to certain keywords - enabling me to sell to end users almost on a daily basis. Ex. "London Scaffolding" - would generate business emails for scaffolding companies based in and around London. I have just purchased an Imac and would like to know if anyone knows of a capable software app/program that is capable of performing this task (extract email addresses based on keywords/search engine searches). Would highly appreciate any guidance anyone could give us.