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.
wrack rack wrick wreak wreck reck raku raki rick rake ruck rock rakee rocky rickey rag rec roc raga ragg reek rook ruga ryke
rack wrack raku reck rick ruck pack rock wrick wreak tack wack wacko whack whacky shacko raki rake mack wreck lack back quacky quack jacky jack knack hack sack tacky wacke wacky whacko shack yack