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.
pip pipy pipe pop pup pep pap peep pupa papa pope poop pepo pupu papaw pappi pappy peppy poppa poppy pupae puppy pawpaw