A 70 - 200 zoom lens is a must have lens for all photographers. If you shoot a Canon dslr camera you won't go far wrong with the 70 - 200 f2.8L IS USM lens. This is a very popular lens amongst professional photographers and when you see what this lens is capable of it is easy to see why.
Another lens on my list, Canon 70-200mm f/2.8
Top Rated Gear Tokina 12-28mm f/4.0 AT-X Pro DX Lens for Nikon
Tokina 12mm - 24mm f/4.0 PRO DX Autofocus Zoom Lens for Nikon Digital SLR Cameras
82mm MultiCoated 3 Piece Filter Kit UVCPLFLD for Canon Digital Cameras Which Have any of These Canon Lenses EF 1635mm f28L EF 2470mm f28L *** Check this awesome product by going to the link at the image.