I've taken a list of English words, and examined each of them to see what they sound like (using the PHP metaphone function). This page lists the most common metaphone codes, along with their words. You can also search for a word of your own, and see which words sound similar - and which ones rhyme, and which ones alliterate.
staff stiff stuff setoff stuffy stiffie staph stave
staff daff daffy taffy teff tiff toff tuff caitiff cutoff putoff setoff stiff stuff shutoff
satay seta setae staw stay stoa stoae stoai