The first step to updating a price is finding the associated Exchange namespace page. All of these pages are the item's name prefixed with "Exchange:". The easiest way to find the Exchange page you are looking for is to search the wiki for the article on the subject. From here, look at the infobox (the large table on the right) and find the row that has the Exchange price. Here, you will see the current price we have stored on the wiki followed by "(info)". Click the word info and it will lead you to the appropriate Exchange page.