To copy a homepage from a previous auction: Go to Event > Home Pages and select "Home pages from past auctions" from the Show Home Pages for pull down menu. From there, select a page and click the Copy to Current link. Once the page is copied, you'll be taken back to your current auction's Auction Home Pages section.
To copy an email from the previous auction: Go to Promotion > Create an Email, select "Email Messages from past auctions," and click Update list. Select an email and click the Copy to Current link.
To copy an auction item from the previous auction: Go to Items > Copy Past Items. Select an Item and click Copy Selected to Current Auction. The item will be placed in the Draft section of the Items tab for further editing.