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.
cassia casa quassia caws case coss cuss cays quass cause cosie gauss gassy quasi cusso causey cuisse gawsie gussie cos gas kas
cassia quassia ossia tassie poussie massa byssi ossa messiah assai assay bassi bioassay essay fossae issei gussie lassi lassie fossa lyssa dassie missay tussah