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.
crock croc crick cruck crack croak crook carack cracky croaky cark carrack cork carioca grok crickey creak creek cargo corky crake creaky crikey curacao curacoa karaoke crag grog kirk
rock frock crock brock trock roc wreck croak reck broke rick croc ruck brook crack arrack rocky rook derrick drouk taroc track troak troke carack crook hayrack grok euroky wrack iroko barrack carrack brick prick rack crick wrick cruck heroic rerack dreck duroc tarok trick hayrick truck
crow cocker cockier rocker rockery rockier