Wow, if I were in your boots, I would defintly look at a Canon EF 100mm f2.8L IS USM macro. The cost may seem a bit high, but you will use the IS option more than you may think. The non IS model, lens wise is good, but you will find in bushes, shrubs, rose bushes, it is much more comfortable to shoot hand held than with a lens camera and tripod. The Canon EF 100 "L" lens can drill down to 1:1 for those tight macro images. If you decide to shoot some bugs, you can get within 11.5 inches and still have great focus, any closer, you'll need a extenison tube. Not knowing what you are using for your landscapes now, I would suggest a Canon EF-S 10-22mm f3.5-4.5 USM. This lens is razor sharp, and considered a Ultra wide angle. It can also be used for close-ups, and portraits. For some real close up work you may want to use a set of extension tubes. The EF-S 10-22 does not come with IS, so shutter speeds below 1/250th second must be used, and a high ISO to keep jitter down when hand holding. You can always use a tripod for the landscapes you may want to take. I use mine even in low light to get some rather nice after dark city scapes of New Orleans.
