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.
tuffet tuft taffeta tufty tiffed toft duvet daffed defeat doffed taught tofutti toughed
buffet haffet whiffet tuffet fet whiffed feet ruffed reffed pouffed pfft miffed puffed biffed huffed daffed fete quaffed defeat taffeta cuffed chaffed chuffed feat effete boffed tiffed soffit safety gaffed riffed buffed doffed piaffed naffed offed baffed haffit muffed feoffed luffed waffed coiffed feta cheffed yaffed
tuff duff taffia taffy teff tiff toff toffee toffy tufa stuff stuffy