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.
capris capers cappers caprice coappears capoeiras gapers cooperies copras copers coprahs copiers coppras cuprous coppers coopers cuppers gawpers cupreous keepers kippers copperas guipures koupreys quippers
capris apers rappers copras japers whappers pipers boppers hoopers tappers lippers keepers coppers diapers mopers paries hoppers coopers sopors pries perries leapers peeries aporias vaporise poppers gapers mappers peris ropers shapers lopers apres yaupers shoppers chippers whoopers uprise topers tapers dippers zappers spurries sippers cypres rippers wipers vipers pars toppers duperies supers sapors reprise peepers parries knappers gyppers nappers capers papers paris quippers aperies hopers roperies prise loppers cuppers poperies fopperies apiaries priss lappers hypers cappers soapers cooperies pooris loopers moperies zippers copers gawpers lepers tapirs heapers beepers peppers weepers japeries coppras rapers choppers apprise kippers pros purs nippers jeepers naperies gippers moppers puris paupers reapers cyprus spurs dopers topiaries vapors yappers whoppers repros wrappers sappers spars suppers diapirs dupers tippers uppers whippers cheepers shippers yawpers
caper capoeira capper coappear copra coprah