For my King James Pure Bible Search (KJPBS) software (http://www.purebiblesearch.com/), I use the SoundEx algorithm for fuzzy search. Though, in my software, it doesn't really have do "searching", per se, as it already knows every word in the text in all of its forms and so the "search" is really nothing more than a word filter that filters what's in the drop list. So it's doing "real time live searching" of the text as you type.
If you enable SoundEx in the configuration options of KJPBS and you enter "btr", for example, you'll see things like "better", "butter", "bitter", "betray", etc, in the drop list.
Though I also accept wildcards too, like "*" and "?", even without SoundEx enable.