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.
diadem diatom datum tedium daytime
diadem deem deme demo demy adeem edema idem madam modem odeum oedema redeem satem
dad did dada daddy dado dead didie dido didy died diode dita duad dadoed