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.
flesher fleshier flasher flusher flashier fletcher foolisher filcher
flesher lasher slushier slasher lecher lusher blusher flasher flashier fleshier flusher foolisher clasher plasher plashier plusher plushier polisher sloshier welsher
flesh fleshy flash flashy fleche flush