Referring to your other post, I think you should get the structure of the database fixed. Sending multiple emails is the simple part. It would be a simple script that loops thru the found records and sends each one an email.....also in The Missing Manual.
With Send Mail there are also ways to reference the email addresses of the current found set--the records you just found by performing your find. There would be no need to copy or export this data if you use Send Mail from inside FileMaker to send out the email.