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.
whatsis
whatsis fatsos footsies ketosis mitosis patsies petsais potsies ptosis stasis tatsois tootsies shiatsus
whats wats waits watts wheats whets whits swats twats