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.
cocoon cogon cocain cocaine cockney coigne coquina
cocoon coon tycoon racoon con coni deacon goony rockoon cogon recoin logon goon coin cone beckon cony macon beacon racon icon neocon reckon lagoon recon bacon scone conn
coco cocoa coca cock cocky coocoo cook cookey cookie cooky acock rococo