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.
guesser gasser cusser gassier queasier causer kisser goosier gauzier causerie queazier gazer caesar cosier kaiser quasar caesura quizzer
guesser lesser dossier sissier sassier pussier passer messier cusser leaser mossier lassoer kisser gassier gasser tessera tusser chasseur masseur geyser issuer massier teaser dosser seiser reissuer pisser mosser hissier mussier lessor bossier fusser fussier hisser tosser wussier cheesier ser
guess gauss gussie gussy agues