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.
senator sentry sanatoria santour santoor sanitoria santir sender center santur centre century centaur centare sanitary centaury ceinture sanitaria centaurea sonneteer sunder sonder snider sinter sander centra sundry sandier santera santero saunter sounder
donator senator genitor janitor cantor contour mentor minatory monitor santoor santour chantor
senate sent scent seniti sente senti sonata