I tried to achieve this same goal some years ago, but had to stop because PDF files were usually bigger than available heap size on Java ME Virtual Machines.
My first try was to port iText (itextpdf.com) from Java SE to ME and then use it on my app.
This took longer than what I wanted so I gave up. :(
But then I created a simple txt reader (for UTF-8 encoding) and made it freely available at getjar.com/books (no ads).