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.
leash lash leach leachy lech lush laich latch leech letch loach lich loch lych
deash leash ash rash bash ashy mesh gnash pasha dash resh dashy fash dashi teach washy beach each hash pash kasha quash lash leach mash mashy meshy cash peach reach gash sash wash sheesh
lea flea ilea leal leally olea plea