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.
sir sire sirra siree sieur sirree ser sri soiree sierra sirrah sear sora sari suer sour sori sera cire sere seer sore sura soar sure cirri zaire serow surra serai surah saree saury sorry serry sorrow souari surrey zooier