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.
spues supes spaes spies spews sipes spouse speiss speise sops sups sips spas saps soups spice seeps space cepes soaps spays sepoys spacey specie spicey sepias hyssops suppose seapiece spaz
spues pes pus quippus kewpies cowpeas tapes lopes lupous coypous pappies nappes capes pews dopes hoopoes opes japes gapes mopes hypes copies spews ripes puce pipes yippies shoppes topes chippies chappies tawpies wipes whoopees types pies peso tepees rapes rupees pappus sipes pups poppies peas loupes pees copes hopes taupes epees guppies weepies lupus topees shapes quipus jupes coypus koppies pehs popes coupes supes apes peps puss puppies chapes hippies spies spaes cepes ropes rappees pupus veepees cowpies pappous yipes opus nappies napes buppies dupes teepees toupees whoopies cheapies yuppies