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.
chetahs cheetahs cheats chits chuddahs shittahs chats chateaus chads chides sheets chutes chotts chitties shots shads shits sheds shuts shades shoats shoots shotes shotts shouts shutes shadows shiatsu
cheetahs chetahs etas betas bettas fetas getas lotahs pietas reatas zetas shittahs tas
chetah chaeta chaetae cheat cheetah