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.
marishes marshes marches marchesa marchese marchesi merches mariachis
marishes perishes cherishes nourishes parishes brushes trashes gurshes brashes qurshes creeshes crashes girshes freshes crushes rishis rashes reshoes qurushes marshes rushes reshes orishas riches rushees