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.
brash brashy brush brach brushy broach breach bearish boarish boorish brachia birch breech broche brooch brioche barouche birrotch
rash brash crash trash brashy resh poorish perish sourish currish boarish orach whorish trashy bearish qursh gursh marish marshy noirish rush crush boorish parish harsh brach currach nourish brush moorish girsh qurush wearish marsh frosh queerish fresh garish fairish cherish