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