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.
gainsay gains guanays kains cains guans quinsy guanos goannas guanase guineas gayness kins guns cans kanas canes kinos gowns kaons canso koans kinas coins goons kines quins kanes cannas canoes kinase koines queans quoins gooneys goonies gunnies quinoas
gainsay quinsy linsey unsay chainsaw ins