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.
gripes grippes grips gropes cripes grapes gorps groupies groups crepes crapes grappas croupes crappies croppies creepies crops corps craps carps carpus corpse corpus creeps croups kreeps carapace croupous
cripes gripes tripes ripes tropes herpes croppies traipse towropes trapes harpies crappies grapes chirps drips creepies groupies grips hyperopes pyropes serapes tripos crepes crapes liriopes ropes rupees frappes rappees drapes rips sarapes troupes preppies trips drupes euripus gropes croupes grippes rapes sharpies
grip gripe gripey grippe grippy gripy cripe gorp grape grapey grappa grapy grope