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.
popsie pops poppies popsy poops popes poppas pappies puppies papoose pappose pups pips peps paps pappoose papas peeps pepos pipes pupas pupus papaws pappus pappous pawpaws
popsie psi pase apse appose poussie pose pies oppose koppies pice buppies reoppose spice suppose tawpies whoopies cheapies yippies lipase coppice hippies pappose cowpies guppies kewpies lapse nappies pappies copse copies poppies puppies repose spies depose weepies chappies chippies yuppies
pop poop pope poppa poppy epopee epopoeia