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.
secure scaur screw score scree scour sucre scare squire scarey square screwy scurry scry scar skier siker sugar scary sacra saker soucar scoria seggar sowcar soaker seeker sucker scarry skerry sacker sagger sicker sugary cicoree saggier saguaro soggier suckier
secure cure cur decree fiacre daycare quire squire figure acre scare recur nacre maugre lucre ligure score curie quare crew core care ocrea require scaur scour screw curr scree square sucre decare decury