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.
coypus coypous cops copious copes coops copse coups coupes copies copays cowpeas cowpies kops caps cups capes capos goops capias cuppas koppas quipus coppice koppies quippus
coypus pus yips yaps typos spues pups hypes hypos hyps puss gyps gypsy quippus coypous quipus lupous lupus opus pappous pappus pupus types typps yeps yups
coypu coypou cop coop copay cope copy coup coupe cowpea cowpie scop scope