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.
cardoon cardon cartoon cartoony carton cordon croton crouton carotin carotene carrotin craton garden guerdon cretonne gardenia guardian gueridon cortin cretin gradin creatin curtain gradine quartan
lardoon cardoon proton radon redon bourdon bradoon bridoon fordone cartoon cardon cordon croton guerdon gueridon lardon pardon teardown
card caird cardia cardiae cardio cared carrot carroty credo acaroid