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.
spans spawns speans spins spoons spense spines spinous supines spinose sapiens spinneys spoonies spinnies spooneys sappiness soapiness soppiness spence sapience sapiency
pans kneepans japans teopans spans taipans copens pansy panes pains paeans jupons spins repins ripens tiepins lippens happens spawns pawns pens papains deepens peans youpons opens pins lapins coupons shippens speans pians puns pippins pons reopens cheapens lupins yapons lipins pianos capons gipons weapons chopins shippons yaupons yupons
span spawn spean spin spine spinney spinny spiny spun