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.
sameness seaminess someones semens cymenes saimins siemens simonies somans simians simoons summons symbions
gameness sameness tameness lameness gaminess chumminess dimness homeyness roominess someones nimbyness gemminess loaminess liminess gumminess riminess hamminess meanness cymenes hominess numbness seaminess demoness dumbness foaminess commonness womanness humanness yumminess