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.
pish poisha push posh pash pshaw pushy pitch pasha pitchy pech pacha patch patio peach poach pooch pouch
beauish fish cuish knish pish dish whish wish sh