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.
quietness quietens cuteness gaudiness goutiness ketenes ketones cutaneous cattiness cutins coetaneous guidons kidneys kittens codeines goodness quittance
quietness meetness wetness retenes hiddenness fattiness fatness bittiness liteness battiness lateness hotness nudeness nattiness retunes rottenness pottiness ruttiness soddenness suddenness doughtiness tautness muteness haughtiness cattiness whiteness witness woodenness patness knottiness fitness matiness wideness ketenes pettiness dueness nuttiness ketones leadenness mateyness meatiness cuteness jettiness whatness mootness wittiness goutiness neatness redness retines rootiness rudeness cetanes sootiness dottiness tattiness titaness chattiness