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.
replow repel reply repeal replay repoll reapply rappel ripely ripple ripply ropily roupily
replow plow pillow pillowy plew ploy polo deploy diploe tapalo tupelo
rep reap repay repo repp arepa crepe crepey crepy prep prepay preppie preppy