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.
setoff staff stiff stuff stuffy stiffie stove
toff cutoff shutoff setoff putoff dieoff doff teff tiff tofu tuff caitiff leadoff staff stiff stuff toffy
set seat seta setae sett settee stoa stoae stoai stow suet suety