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.
goniff gonif gonef gonof ganef ganof gonoph connive
sniff goniff knife naff naif neif vinify gonif minify reunify runoff sniffy snuff unify
gonia coni goanna gone goon gooney goonie goony gown agon agone agony