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.
rotund rotunda redound retuned ratooned rattened redonned retained retinued rattooned reattained retint rodent reddened redenied retinite retinoid
rotund tend tuned attend attuned coattend redound retuned rotunda stand stound stunt
retune rotten routine croton crouton protean protein proton