Possible Clues:

• Concur, assent
• What the like-minded do
• Terribly eager to correspond
• Eager (anag)
• Silver surfer latterly starts to email -- expats correspond
• Be of the same mind it's just about one from Athens
• Say "uh-huh," say
• Give the go-ahead
• Harmonise and transpose reduction of Meyerbeer gavotte
• A premature ending brought to European match