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.
plenty polenta plant plaint planet pliant pollenate pollened planed plained planate planned palinode
plenty leant talent slanty salinity relent lenity lent lento linty blent eluent felinity flaunty flinty fluent violent client glinty polenta salient silent diluent cholent
plena plan plane pleon poleyn spleen spleeny splenia splenii