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.
tartar tartare tarter tartier triter darter trotter torture tardier troutier trattoria territory trader dirtier tireder traitor treader treater toreador torrider
mortar tartar charter tartare sorter martyr darter sirdar sardar porter perter pearter mortary quarter sartor retear curter courter carter hurter barter rotary garter tarter shorter
tarty tart start stared dart tardo tardy tared tarot tarred tarried teared tort torta torte tret trite trot starred tattered