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.
graffiti graffito graft gravity graphite kraft grift craft crafty grivet gravid gravida gruffed gravidae croft cravat graved
griff griffe gruff gruffy agrafe agraffe