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.
savvier saver suaver savior saviour savor sever siver safer savory savour soever sigher severe savoury sofar cipher safari sphere sphery suffer sypher zaffer zaffir suffari
savvier vier bouvier heavier jivier leavier levier livier riviera riviere wavier