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.
lupin lupine lapin lipin loupen lippen
lupin pin coupon lapin lipin loupen lupine papain pippin jupon repin cioppino spine supine upon chopine youpon rapini pion apian pepino pine pina pian pein pain opine piny rapine rappini repine spin spiny tiepin chopin yaupon yupon