I played around with PDF::FDF::Simple and I couldn't get it to extract text from PDF files. I thought that FDF was just a subset of PDF but there must be more to it than that. Then I looked around for free PDF-to-text tools and was surprised to find that there aren't many that are truly free. Ghostscript may be your best free option. It apparently has a tool for getting text from PDF documents. Another one I found is a Java tool named PDFBox.