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.
defuel devel deafly defile deflea duffel devalue dewfall devil dayfly daffily teughly
fuel refuel biofuel defuel feel woeful fell waeful rueful refel foul awful refell feal lawful afoul joyful refeel rifely safely befell flue duffel full wifely befoul woful