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.
scart scared secret secrete cigaret scarred security skort scrod skirt squawroot cigarette scored screed scrota sacred scried squirt saggard scoured secured skirret squared sugared saggared saggered scurried skywrite skywrote suckered
cart scart teacart cigaret keycard ecarte bogart quarto quarte kart carat karat curt crit carte caret card secret quart
scar scarry scary scare scarey scoriae escar sacra scaur score screwy scree scoria scry scurry sucre screw escrow