Adding .txt email lists into Aweber?

Hey. I have a small question:

If I have a list of emails in a .txt file, is there any easy way to add all these emails into Aweber?
Oh, and the list is kinda big.. I can't submit them all manually.
Also, would I be allowed to make a script that auto-submits each email to the opt-in form? Would Aweber see that they're all from the same IP and ban me?

Actually, never mind.
I just realized that having 25k subscribers costs like 130$.. And I have 50k+ emails to add. It's going to be WAY too expensive.

How would I go about sending out emails, then?

anybody have a solution?