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.
garish gursh currish grushie carritch queerish qursh crush crash caroch creesh grutch grouch qurush caroach caroche carroch grouchy
boarish queerish fairish moorish wearish boorish perish nourish bearish cherish currish marish garish poorish noirish parish whorish sourish rush crush gursh crash girsh trash marshy brush marsh rich rishi rash qurush resh orisha harsh frosh qursh brash fresh