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.
kaffir kafir kefir gaffer gauffer quaffer caviar coffer goffer caviare goofier coiffeur coiffure
kaffir zaffir fir doffer whiffer deffer deifier coffer zaffre buffer iffier gaffer gauffer feoffor chuffer goofier goffer kafir miffier offer puffer reefier reifier suffer zaffer chaffier huffier quaffer refire fiar fair leafier niffer beefier afire affair fire feoffer reoffer piaffer puffier zaffar kefir buffier daffier defier differ duffer chaffer chauffer chuffier