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.
griddle cradle curdle gradual grittily quartile greedily gardyloo cordelle gradually credal kirtle cordial creedal crudely curtail greatly
riddle griddle raddle reddle ridley ruddle bridle girdle treddle