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.
cowl col cool coil coal coly cola cole colly coyly coaly cooly coala collie coolly coulee callow coolie clew kolo caul goal clay clue calo kola claw kohl cloy cull gaol glow koel call calla cully golly koala quoll
bowl fowl howl jowl cowl owl yowl