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.
catchy catch cache coach cutch cachou cash couch cooch cushy ketch cashaw cashew cashoo gauche gaucho gotcha quaich quitch gouache
bitchy botchy fitchy witchy catchy patchy tetchy itchy pitchy aitch etch hutch duchy beachy poachy ketch gotcha fitch letch mutch litchi bitch nautch patch peachy datcha hitch pitch hatch ratch vetch chay vichy retch watch rotche reechy notch butch witch tach ditch cutch techy wretch catch achy pouchy fetch botch tech dutch leachy rotch itch natch hootch beechy hotch batch latch quitch touchy match yechy