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.
pyropes props preops hyperopes propose preppies preps hyperopias prepuce priapus purpose porpoise perps prepays
gropes tropes towropes hyperopes pyropes ropes liriopes herpes harpies cripes drupes sarapes drapes rapes crops drops troops trapes troupes hydropsy croupes dropsy props preops croups hydrops crepes tripes crapes droops roups serapes gripes groups grapes ripes sharpies