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.
safest suavest savviest sophist sufficed suffused
fest buffest liefest chuffest deffest deafest chiefest safest rifest offset leafiest huffiest vesta leaviest jiviest divest fiesta vest reefiest buffiest iffiest beefiest livest feast chaffiest fast feist nighest roughest waviest devest highest daffiest fist goofiest toughest naivest heaviest savviest suavest puffiest miffiest lievest revest chuffiest