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.
carrotin carotin carotene cretin croton cortin carton cardon cartoon cortina cardoon crouton creatin creatine cartoony cordon craton gratin curtain gratine keratin quartan cretonne gratinee guardian cowritten garden gradin
carotin carrotin serotine ceratin rutin ferritin cortin cortina cretin croton curtain gratin keratin martin martini pertain protein proton certain serotiny
carrot carroty carried corrode corrody garrote garrotte acaroid scarred