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.
chuff chuffy chaff chufa chaffy chef chafe chief
huff chuff quaff ruffe puffy pouffy buff buffi buffo buffy huffy bouffe cuff tuff guff luff luffa muff pouff pouffe puff ruff duff whiff chufa quiff chaff chuffy