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.
grippes gripes grips gropes cripes grapes grappas crappies groupies gorps croppies crapes groups crepes croupes creepies craps carps corps crops carpus corpse corpus creeps croups kreeps
grippes rappees ripes frappes crappies cripes croppies gripes liriopes preppies tripes
grippe grippy grip grappa gripe gripey gripy