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.
cyprus cypres cypress sprues spurious saporous spurs spars speirs spores speers sopors sprays spares spiers sprees sparse spruce sprucy spires spears spoors sapors supers sapours zappers sippers suppers soapers spireas sappers zippers sparrows spiraeas spurries suppress
cyprus hypers chippers nappers lopers lappers uppers vapors mappers purs dopers papers gawpers hoopers spurs beepers vipers gyppers saporous lippers paupers apres vaporous biparous coopers peppers cappers kippers lepers whoopers yaupers shapers wipers whappers topers tapers diapirs suppers spars sappers cypres shoppers jeepers hoppers tappers zippers soapers ropers boppers poppers coppers rappers cuprous repros copras moppers knappers leprous cuppers pipers copers peruse parous praus peepers loopers sapors japers heapers porous hopers pros keepers papyrus dupers pareus mopers viperous weepers leapers loppers nippers choppers capris supers quippers capers rippers gapers reapers coppras rapers pars wrappers sopors diapers tippers gippers yappers whoppers apers sippers sprues zappers dippers tapirs toppers whippers cheepers shippers yawpers