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.
kefir kafir kaffir goofier
kefir fir chiefer deifier defer zaffir refry refer reefer miffier fair fiar fire affair afire beefier buffier huffier iffier goofier kaffir kafir leafier liefer puffier reefier refire reifier daffier defier chaffier chuffier