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.
nappes nappies napes nappas naps knaps napas neaps nips knops neeps nipas
nappes shoppes pes quippus gapes apps cowpies copes pews rappees loupes koppas napes jupes coupes pappus peas pies spues hypes hopes pehs rupees pees ripes weepies yippies topes hoopoes cheapies tepees chapes whoopies tapes types peps peso chuppas spews tawpies poppas pups opes dopes pips pops cuppas kappas sipes hippos kewpies supes nappas capes ropes copies apes lopes puppies mopes buppies repps epees japes guppies spaes koppies cowpeas veepees yipes spies toupees pipes popes dupes pappies rapes poppies teepees cepes nappies typps hippies whoopees taupes wipes chappies topees chippies shapes paps yuppies
nappa nappe nappie nappy nap knap napa nape neap nippy snap snappy