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.
quiff quaff cuff cuif guff coiffe guffaw quaigh kif caff coff coif gaff kaif kief kufi
quiff iff coiffe cuff cuif quaff iffy guff jiffy muff miff pouffe puff riff ruffe duff tuff chuff luff jiff huff miffy buffy biff buffo buffi buff bouffe biffy luffa huffy pouff pouffy puffy ruff diff tiff whiff chuffy