How would you suggest I approach calling in this loan?

I loaned an acquaintance $480 a year and a half ago. She needed the money to pay for training for her insurance license. It was a leap of faith for me to loan her the money, but it seemed that she’d easily be able to pay me within the timeframe we set up (7 months). The interest we agreed on was just $20, and it was basically a favor, an act of good will.

She completed her training, worked at the insurance job for a month or two, and the job ended (I think she just wasn’t successful in it – not sure if she quit). 4 months late, she paid me $100 of the $500+. (The original agreement said that she would pay $5/month for every month she was late, if that came up.) At the time she said she would send me something from every paycheck at her new job. That was 8 months ago. She hasn’t sent anything, or been in communication. I sent two polite e-mails over the last 6 months, and she did not respond to either e-mail.

I’m not sure how to respond, and looking for ideas and advice. Would you suggest I write her something more confrontational to get a response? Take legal action? How would I do that? I’m at a loss here – no pun intended.

I was in good financial shape when I made the loan. I’m not in such good shape now, and could use the money. Thanks for reading all this, and for offering your suggestions!