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.
smack smock sumac samek smeek smoke smoky samekh smokey sambuca sambuke smog smug
mack smack mac umiak umiac tomback tambak sumac bemock make mako mick mock muck amuck oomiack hammock hommock rumaki hummock remake smock gimmick tambac comake tombac mammock tombak oomiac umiack oomiak shmuck