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.
groan gran grain grown grana groin granny grainy groyne garron grannie guarani grin guarana crane crone crony kroon krona green krone crown croon garni gurney crania curran greeny cranny corona krooni greenie coronae carrion carn corn curn karn kern kirn
groan roan ran purana pyrone grown buran prion hyperon brain brawn loran neuron drawn pirana durion bran pereon serrano marrano morion krone heron chorion turion terrane drown diuron saran giron frown furan furane hereon trona guarani morrion crane crony crown garron gran irone carrion irony heroin curran boron iron gyron croon rani borane groin brown perron corona rain crone guarana baron grain prawn saurian barony virion reran grana murrain pyran maroon marron parian krona neurone moron drain prone durian kroon terrain train sierran trone whereon drone shoran