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.
bowfin boffin biffin bovine buffoon
bowfin fin define ruffian refine puffin muffin coffin boffin caffein biffin affine foin fino fine fain tiffin