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.
pushup
washup pushup ship shop bishop catchup ketchup matchup mishap reship teashop touchup toyshop
pushy push pash pasha pish posh pshaw