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.
sous souse sos soys suss sows sues sis seas sass cess says sees sews seis saws cissy sassy sauce saucy seise sissy
meous miaous nous pious sous yous os us