Is it computationally possible to voice-recognize and word-tag-time-align audiobooks to their actual text?
The fact that humans can understand audio books shows that it is computationally possible. This does not make the problem easy for an AI. It also does not mean that you can write a formalism of the language in audio form for parsing. Anything involving audio / recordings is going to involve lots of fuzzy data. This is not generally what someone would call parsing, but instead speech recognition. If you can properly recognize words in the correct context then the rest of the stuff you mentioned like dictionary lookup, and moving around a book is basically trivial. 

It is easier to do this if you already have the words though. I would recommend something like splitting the audio based on breaks, and then applying speech recognition on each section to make sure the word matches the audio that was split. This is to check if errors in splitting exist. If there is an error where the word does not match the audio a human could be prompted to manually split them.