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.
nadir nattier needier kneader gnattier niter nuder nitre nitro needer nature notary neater natter nitery nodder knitter nettier niterie nittier nuttier knottier
nadir faddier dire bawdier lader beadier boudoir beader reedier stair ruddier deedier reader padri tidier needier weedier kneader chadar moodier chadri leadier shadier madre dairy header radar cadre giddier gaudier hetaira headier hoodier readier seedier rowdier deader padre fader dowdier deair wader muddier woodier midair chador leader shader loader shoddier
nada naiad nidi nodi nudie indie