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.
wartier warder wordier weirder wiredrew
artier partier dirtier courtier shirtier wartier heartier purtier chertier tartier quartier horrider tarter lardier nerdier cowriter carrotier curdier garroter frettier ferreter barrater tardier darter troutier joyrider frater grottier groutier grittier carter krater irater fruitier perter torrider artery brattier charter garter quarter prater arider rider hurter courter curter barter sorter rater triter derider writer hardier ureter rewriter grater lowrider crater portiere rattier rootier ruttier parroter pearter porter wordier narrater prettier shorter
wart warty wearied swart swarty