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.
clouter coulter clutter cluttery cloudier colter clowder gloater cloture clatter colluder clattery cloddier kilter colder kelter culture caldera quilter glitter coleader collider gleetier glittery guiltier collator gauleiter glider golder kultur gladder gladier guilder
flouter clouter slotter poulter plotter molter coulter clutter looter lotter louder allotter balloter bloater loiter bolter floater fluter flutier flutter vaulter jolter blotter colter gloater moulter polluter saluter diluter
clout clot calotte cloot clotty cloud cloudy culotte glout