I am trying to modify the form for "item-send-friend.php" because I would like to add additional fields. I would also like submitted results to always be sent to the seller. Is there a processing file that controls how this form is processed so i can specify the new field values and where the form is supposed to be sent?

@Zig220
This is unfortunately hardly doable and would most probably require modifications in core & email templates.

@Zig220
This is unfortunately hardly doable and would most probably require modifications in core & email templates.

I would like to make a custom form from scratch instead of using "item-send-friend.php" .
Can you provide the code to obtain the "SELLER'S" email address so that I can create a custom form from that will email out to the seller?

@Zig220
That is not as easy, best way is to do it via plugin and create custom link for that.