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.
secured scoured scurried sacred scared scored screed scried secret squared sugared squired scarred secrete security saggered suckered scrod skirred saggared scart scrota squirt cigaret saggard skirret
cured secured curd cred decried curet squired screed cried scored sacred recurred liquored cared cored credo curdy creed leaguered required acred scared augured scoured figured scried curred squared nacred decreed quired chequered