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.
radula radulae radialia raddle radial radiale readily radially redly ratal ratel riddle rutile ridley ruddle retail rattle redial reddle ritual rudely rattly rattail reedily retally rowdily ruddily ruttily ritually
cedula radula doula dual duel dulia dull duly eidola medulla module moduli modulo nodule radulae
rad roadeo trad kraut grade grad irade fraud brad roadie road radii ready readd read raid radio orad trade