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.
groutier grouter grottier grodier courtier garotter grittier garroter garter grater carrotier greater gridder courter greeter gritter cruddier greedier quartier curter cruder grader crater krater carter critter curdier guarder quarter crowder cowriter criteria carder corder
groutier troutier chertier rattier partier frettier grottier curter rootier router ruttier artier brattier bruiter reutter prettier heartier fruiter hurter carrotier courter courtier grittier grouter quartier portiere purtier tartier fruitier dirtier wartier shirtier
grout grouty grot croute garote garotte griot groat grotto grotty