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.
spoon spoony spooney span spin spun spawn spean spine spiny spinny supine spinney
poon spoon youpon yapon shippon weapon upon depone spoony coupon capon jupon gipon pony pone pion peon yaupon yupon