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.
whimsies whimseys wamuses wammuses
whimsies emesis pumices momuses koumises kumyses muses amices gummoses bemuses amuses embassies tmesis demoses wamuses zymosis phimosis zymases chemises cimices missies mises hummuses nemesis mimesis gummosis koumyses camases humuses camises hommoses vamoses phimoses tamises demises wammuses zymoses whimseys semises chamises remises shamuses
whims whimsey whimsy whams whomso swims