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.
order ordure orator oratory oratorio
birder harder murder reorder boarder herder girder corder yarder hoarder border guarder warder larder order weirder carder grodier nerdier marauder garter porter barter ruder lardier curdier tardier broidery greedier prouder quarter courter derider redear shrewder shorter wordier broider ruddier redder cruddier readier lowrider joyrider hurter tireder breeder pearter broodier brooder arider rudery grader carter trader curter perter reader cruder horrider hardier prodder sardar prudery sorter darter sordor parader treader rudder crowder braider broader torrider rider tarter reedier forrader ridder gridder ardor raider rowdier charter shredder sirdar