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.
lassoer laser leaser lesser lessor lacer loser lacier lazier looser lousier lazar leisure
lassoer bossier guesser kisser lesser lessor massier cusser pisser mosser pussier sassier sissier dossier tussor tosser wussier gassier issuer mossier messier hisser voussoir fussier fusser masseur mussier passer gasser pissoir reissuer scissor dosser tusser tessera tussore hissier chasseur ser
lasso lass lassi lassie class classy glass glassie glassy las