I have been asked by a friend to photograph her mom's wedding since an emergency came up with their professional photographer. By no means am I a pro. I'm just a mom that takes decent pics of her kids. I have a Nikon D5000 but only a standard kit lens (crappy zoom). I'd like to purchase a lens for the occasion. Can anyone give me advice as to which lens would be suitable? I guess I should also look into getting an external flash as well, so I would appreciate any info in regards to that. I've never photographed a wedding (and they are very well aware of that) so I would be very grateful for any pointers. It will be an outdoor wedding at the Daytona Int'l Speedway in Victory Lane at 4pm and the reception will be indoors. I'm in a panic, the wedding is THIS Sat. Please help!! Thank you , in advance!!