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.
cooch coach couch cosh cache catch cutch cachou cashoo catchy gotcha gouache cash gosh
hooch mooch pooch cooch mocha whoosh loch rotch couch pouch loach ouch notch mouch hotch boche poach coach hootch roach vouch touch botch woosh
coocoo coo cooee cooey boocoo coca cock cocky coco cocoa cook cookey cookie cooky chock chook