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.
cation caution kation coition cushion cushiony katchina cochin
cation coition lotion motion nation tuition kation ration caution potion notion suasion fashion basion fusion lesion cushiony cushion vision titian nasion