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.
untidy untied undid united unaided unnoted uintaite unideaed undead unadded unneeded
untidy nitid bountied entity vanitied quantity lentoid manatoid mantid noontide dentoid untied