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.
rumen ramen rumina reman roman ramona remain romano romaine
numen rumen lumen men laymen lomein amen lawmen ramen mien mean foemen cymene semen menu demean women yamen bemean meno limen cowmen cumin baymen noumena bowmen nomen hymen omen seamen vimen daimen human tamein showmen yeomen
rum crumb drum grume grum crummy crummie crumby brume ramee brumby arum rummy rumba romeo rime trumeau