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.
rappel reapply repel repeal ripely ripple ripply reply replow repoll ropily roupily
rappel appel chapel topple dapple supple spell speel ripple repel reapply popple nipple lapel cupel hopple apply fipple apple appeal appal pele peel peal repeal ripely ripply speil spiel supply tipple tupelo shapely
rappee rap drapey grapy grappa grapey grape crappy crappie crape crap frappe frap wrap repp reap rape drape trap