fee
 

I am a US citizen and will travel to Argentina this week with my US passport. I was born in Argentina - do I still need to pay the fee?

Do you have a DNI....? Check this thread, this issue has already been covered in detail. I think that if your US passport has your place of birth, it normally does, that may be enough for Argentine Immigration... however, question is if the airline will buy that.

Do I still need to pay the reciprocity fee if entering Argentina via land border?

Yes, and by sea too.

can you let us know if you have a problem? My mother is going next month, is also a US citizen, and also born in Argentina.

The airline is indeed going to be the sticking point. Either a DNI, (expired) Argentine passport or a Libreta cívica/de enrolamiento if they emigrated before the DNI was introduced, should be sufficient.

A DNI or the paper/act where the "residencia permanente" is established should be enough to avoid the fee.

Yes it would be a relatively simple process at EZE immigration but in my experience some airline check-in staff might give the person a hard time.

It wouldn't hurt if you can get a hold of a Timatic printout with the permission to have on hand.