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.
sokol skoal scowl skell skill skull socle sickle sickly suckle soggily zooglea zoogleae zoogloea zoogloeae
sokol cool cooly koel kohl kola kolo googol skoal yokel
soak sock socko soke sook souk askoi