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.
fresh frosh foreshow fairish freesia farouche fourchee
resh fresh boorish boarish bearish rush rash currish gursh brash marish marshy noirish parish poorish trash whorish qursh brush fairish qurush harsh girsh crash creesh crush garish queerish frosh marsh moorish nourish perish sourish wearish cherish
fare fere fire fore frae free froe