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.
crumber crumbier crummier crammer creamer crimmer grummer creamery creamier grimier grimmer groomer krimmer gramary grammar
crumber rummer crumbier grummer drummer
crumb crumby crambe crambo crummie crummy scrum