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.
outrun outran outearn outturn outthrown
outrun tarn diatron cittern citrin retorn tern torn turn attorn biotron bittern gittern matron natron neutron outran outturn patron pattern return citron stern waitron
outre outrow outer outthrew outthrow