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.
certain ceratin serotine serotiny sardana sardine sordine sordini sordino
curtain certain pertain tartan carrotin rutin ceratin puritan ordain carotin partan martini reattain retain ferritin reordain martin cortin cortina cretin gradin gratin keratin ratan quartan tartana