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.
shorter shirtier charter chertier shredder shrewder charioteer
porter sorter shorter quartier garotter hurter border barter ferreter quarter mortar grouter order barrater partier perter prater heartier crater reorder courtier rater rioter dirtier tartier trotter wartier charter shirtier frater garter courter grater rooter rootier irater router writer rotter carter parroter artery pearter krater artier corder garroter purtier curter rewriter darter tarter triter ureter charioteer chertier cowriter carrotier narrater
short shortie shorty shirt shirty shored