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.
hoopoe hoopoo hoop hope hop hippo hoppy hippie hap hep hip hup
hoopoe ope whoopie topoi topee dopey dope ropey rope pope nope mopey mope loupe lope coupe cope hope hoopoo tope topo whoopee shoppe