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.
hoopers hopers hoppers heapers
hopers hoopers coopers topers mopers loopers ropers whoopers copers dopers lopers dippers coppers speirs rapers cuppers papers japers rippers coappears gippers sopors apers kippers soapers copras peers knappers boppers quippers gawpers supers spiers gyppers yaupers shoppers shapers chippers wipers sappers whappers uppers dupers vipers tappers sippers suppers gapers pipers wrappers jeepers pears lippers speers copperas nappers peepers rapiers reapers leapers appears poppers paupers keepers nippers moppers tippers copiers cappers capers lappers spears rappers loppers peris heapers reappears hoppers zippers diapers piers perse tapers lepers beepers peres operas hypers peppers mappers zappers toppers weepers whippers whoppers cheepers choppers shippers yappers yawpers