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.
flashy flash fleshy flesh flush fluish foolish filch fleche fleech fletch flitch fellatio ghoulish
flashy plashy lash leachy leash bolshy flash fleshy calash clash goulash plash plushy slash sloshy slushy