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.
daffiness deafness defines dauphines daphnes tiffins deafens divines dauphins defiance tiffanies diaphones divans davens diaphonies defense deveins defence daphnias deviance divinise divinize toughness diaphanous
beefiness daffiness puffiness miffiness leafiness huffiness goofiness iffiness fines vainness defines refines savviness caffeines affines finesse safeness rifeness deafness heaviness waviness fins