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.
rack wrack rake rock raki reck raku rick ruck wreak wrick rakee wreck rocky rickey rec rag roc reek rook raga ruga ryke ragg raggy reeky rekey rooky rugae
back hack jack quack lack mack knack pack rack wrack sack tack wack whack shack yack