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.
martyr martyry mortary marauder moratory mortuary mortar murder mirador murderee
martyr barter charter tartar hurter carter courter curter garter quarter martyry mortar pearter perter porter sartor sorter darter tarter shorter
mart maraud marred married mort amaretti amaretto imaret smart smartie smarty