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.
grossly crossly grassily grisly crassly greasily crousely curiously crusily grizzly crissal creosol coarsely carousel carousal carrousel grisaille cresol cresyl crazily gracile grizzle
crossly grossly rosily brassily erosely furiously variously crassly curiously grassily morosely porously prissily prosily seriously dressily
gross cross crosse grass grassy grouse grows