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.
scaur scar scour scare scary scarey secure sowcar scarry soucar scurry scry saguaro saker cigar screw sugar sacra scree sucre score soaker sicker sagger scoria screwy seggar sacker saggar square squire sucker sugary saggier scoriae suckier
scaur cur car carr decare cure sowcar curr secure gaur acari scary care scare kauri kaury vicar picara picaro recur scar scour soucar daycare decury