Looking on the internet deeply has found these results:

have sent an email is the most popular phrase on the web.

have send one mail 11,520 results on the web	have sent an email 1679,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
It doesn't look like this phrase is very popular! The search could not find any examples on the internet.	You sent an email last night. Jay Carney or someone's office would have sent us an email saying reportable. initially in German, but the English and French versions will follow Admissions sent an email confirmation, and it's just orientation. in which I make a statement in this regard, and I will also duly reject the accusation. I have sent you all an email Anyway, I have sent an email telling everyone that we have class today and I would like you to attend. Mr. Possibilities just sent an email, ten minutes ago.

have send one mail

11,520 results on the web

have sent an email

1679,000 results on the web

More popular!

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

You sent an email last night.
Jay Carney or someone's office would have sent us an email saying reportable.
initially in German, but the English and French versions will follow
Admissions sent an email confirmation, and it's just orientation.
in which I make a statement in this regard, and I will also duly reject the accusation.
I have sent you all an email
Anyway, I have sent an email telling everyone that we have class today and I would like you to attend.
Mr. Possibilities just sent an email, ten minutes ago.