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.
speils speels spills spoils spiels spells spails spiles spales splays spalls spools sepals sapless supples sepalous soapless soupless supplies splice
speils poilus uppiles spoils spiles spells speels repels rappels lapels cupels huipils huipiles appels appeals pails pilus peals pills pilis piles peles peels pupils repeals spails poleis spiels spills tupelos chapels
speil spail speel spell spiel spile spill spoil espial