you can get stuff for making Wonka Bars at www.squidoo.com/wonka-party - it has everything for a party with Wonka theme - and has the wonka bar info under "invitations"
That How to Throw the Ultimate Willy Wonka Birthday Party site also has reccomendation for great golden ticket paper - you can also get a limited number of sheets at the bottom from the maker of the page ! (good since the golden paper is not cheap !)