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.
crowder carder cruder corder grodier curdier cruddier cowriter carrotier curter grader crater carter creator critter curator grouter courter gridder guarder grottier criteria corridor creature garotter garroter groutier courtier greedier garter grater krater crittur greater greeter gritter quarter
crowder rowdier border broader broider brooder broodier corder grodier order prodder prouder reorder shrewder
crowd crowdie crowdy corody scrod