The plural form of email, being an irregular noun, is femail.

If one sent or received mail on several occasions, one would have sent or received several "mailings." The plural of email should follow suit as "emailings"; however, while my ISP's [MSN] spell checker does recognize "mailings" as a valid word, it doesn't recognize "emailings" which leads me to conclude that "emails" was generally accepted early on as a shortened noun (for "emailings") in addition to its role as a transitive verb.

You know what they say. Better to copulate than never.

Actually there is a techy acronym used as the plural for email - TMFE

Too Much F*ing Email