GhostReader is the premier Text-to-Speech solution for the Mac. The program allows you to listen to Text, Word, HTML, PDF and RTF documents (plus in Leopard: DOCX and ODT documents), create personal and educational podcasts by converting text to audio files, convert text to iTunes tracks with the encoding of your choice: AAC, MP3, WAV, AIFF, Apple Lossless, create your own bookmarkable audiobooks by exporting to iTunes tracks, speak selected text in any application using the GhostReader tool palette or a keyboard shortcut.
With GhostReader you can simply point your cursor at text in Safari, Pages 2008, TextEdit, or Mail and listen to the paragraph below the cursor instead of reading, use the included pronunciation editor to modify the way a word is pronounced or to add new abbreviations.
An interesting tool, we can play with. The possibility to record the track I like most. It seems to be possible to do audio books from the written ones you like, though I'm not sure about the quality of the out-coming file. Besides I consider it to be a rather expensive one.