Hello Photo Peoples, I'm hoping for some sound purchasing advice for a (soon to be) first time dslr owner. Basically I've lined up as an entry into hobbie photography a new Canon 450d/XSi. I'm mostly interested in exploring subject/portrait type stuff and some macro shots too. Now obivously the big advantage of a dslr is the ability to swop out the lens, so my real question is: What are the '3 essential' lenses that I should start with? Do people usually buy a 'kit' or save their money for better lenses?