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.
palpi palp palapa polypi plop pulp polyp pulpy pullup
palpi alp jalap jalop galop kalpa kelpie palp polypi salep salp salpa tilapia
pal pally spale papulae papillae papally papal opal pial peal pawl paly pallia paella pall paleae palea pale pail papilla papula papule spall