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.
cosec cusec caseic cossack casque cassock cask cusk
cosey cos case cooees cooeys coos cosie coss cosy cows coys cozey cogs cokes