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.
retread retired retreat retried retard reuttered redried reiterate retort ritard rehydrate redroot
outread tread retread trad trade lettered tired tared dread buttered treed gettered matured cottered metred guttered fettered mitred tyred catered natured pattered pottered retired retreat reuttered stored tattered tetrad tottered uttered watered chittered shuttered triad muttered loitered outtrade treat hatred attired battered bettered bittered featured jittered trued littered mattered metered mitered motored puttered laterad nattered neutered petered tried retried stared sutured teetered tittered tutored waitered chattered shattered yattered
redrew retear retire retiree retore retro retry ureter