in reply to JulieR

Agree with the other comments - You say yours are images of text files. What are you making the text files in? One of the best ways I've found for making accessible PDF files is by exporting from Word documents seems to work well. Exporting from other programs likely can also be made to work - there are some PDF creators and office copier / scanners which do create those "photographs of pages" type PDFs. You can type the text out, or use an OCR program like Abbyy FineReader
⇧