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.
doubt debt dubiety debit debut daubed debate dubbed tubate towboat
doubt bout about cubit qubit obit robot rubout
dub daub daube dauby dobby dobie doby doobie doughboy adobe adobo outbuy outby