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.
square squire sugar sucre scare secure sugary soucar scarey saguaro scar scree saker screw scour score scaur sacra scary scarry screwy scurry sacker soaker seggar saggar sowcar sucker sagger saggier scoriae suckier
quare square acre care quire quaere guar curie cure scare pugaree require fiacre sucre daycare dekare chukar meagre eagre jaguar soucar ligure lucre maugre nacre puggaree saguaro scarey cougar figure secure squire sugar decare chickaree shikaree