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.
difs diffs deifies dieoffs diffuse duffs dives daffs tiffs defis divas dufus doffs davies doofus defuse defies devise devisee diphase divvies devious devs devas doves teffs toffs tofus tufas tuffs
ifs coifs cuifs kaifs kifs naifs neifs reifs rifs seifs difs waifs