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.
safer saver suaver zaffer suffer safari savvier savor sever siver sofar sphere zaffir savour sphery sigher savory savior zaffar sypher severe soever zaffre saviour savoury suffari
safer chafer wafer loafer deafer fer aver afar haver huffier fear faery leafier knifer deifier caver paver laver heaver beaver daffier kafir hoofer goffer heifer reifier chuffier chiefer chauffer chaffier waver whiffer liefer rifer iffier suaver gauffer puffer niffer zaffer coffer deffer fere buffer reaver fifer beefier newwaver quaffer coiffeur roofer puffier lifer reefier suffer raver goofier leaver miffier gaffer saver buffier feoffer quaver defier doffer piaffer puffery reefer refer reoffer offer gofer differ defer duffer wafery weaver woofer chaffer chaufer chauffeur chuffer shaver