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.
flashes fleshes flushes filches fleches fleeches fletches flitches fellatios
lashes slashes clashes flashes leashes plashes goulashes calashes bleaches slushes lushes laches goloshes polishes pleaches blushes flushes leaches bolshies galoshes plushes loaches relishes sloshes fleshes welshes
flash flashy flesh fleshy flush