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.
scion cion son sin sain sine soon sign sinh sone cine sown sonny scena sinew seine scene hyson sienna sinewy sen syn zin sun snaw zone sewn zine sene seen zein sane sunn syne snow zona sawn zoon
cion scion ion con cain coin cone coni conn cony coon lion pion cine chin chon