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.
maar mar mair mara mare maria marry marrow mor mir marrowy mere mure miri mire moor miry mora mura murr more moray murry murre murra morro moire morae moory moira merry mbira myrrh