Just threw together a list of stuff on the B&H Photo site. It’s Nikon cuz that’s what I’m familiar with - a comparable Canon kit would be much the same price and have much the same capability.
Nikon D60 w/ 18-55mm VR kit lens - $605
Nikon AF-S 70-300mm VR lens - $479 (to save a bit you could opt for the 55-200mm, which can be got in a kit with the D60 & 18-55 for an additional $250) There are lots of cheaper tele zooms out there, but you get what you pay for when you’re buying optical glass.
Tamron 90mm Di Macro - $450 (If you’re doing mostly product shots in a studio, you could go for the Sigma 50mm Macro @ $280. In either case you’re going to need some sort of lighting, but you can rig a lightbox with a white sheet and some desklamps with 6500K bulbs)
Nikon EN-EL9 battery - $39
Nikon ML-L3 remote control $17 (need something to trip the shutter when you’re on the tripod doing macro)
Bogen/Manfrotto 190XB tripod legs $130 (cheaping out a bit here, mostly because I can’t seem to locate the 055 series aluminum legs which I think come in around $200)
Bogen/Manfrotto 488/RC0 tripod head $110
Bogen/Manfrotto 030-14 Quick release plate $18
Nikon SB-600 Speedlight (flash) $185
lens pen and a rocket blower $25
2 4GB SD cards $50
Lowepro Nova 170AW shoulder bag $55 (not sure if this is big enough)
Total before shipping $2165
Places to save - the obvious ones are going with the 55-200 instead of the 70-300, and with the 50mm macro instead of the 90mm. That’s almost $400. Thing is, for sports/nature photography you’ll find that 200mm isn’t a little shy on reach. Even the 70-300 is on the short side for shooting things like birds. As to whether the shorter macro lens will work, it all depends on what you’re shooting. Any macro lens that focuses to 1:1 will have the same magnification, but shorter focal lengths will put your subject closer to the camera (really freaking close, to be honest) and alter the perspective. And also potentially complicate lighting.
Tripods with heads can be had for as little as a hundred bucks, but such are not likely to be particularly stable or robust. Go on any photo forum and you’ll get told to buy Gitzo carbon fibre legs ($500) and an RRS ballhead (another $500). The Manfrotto stuff is a decent compromise, but you could go with a cheap one if it’s just going to be used in a studio and you’re very careful (no stepping near it during a shot, no wind, no traffic vibrating the floor, etc). But you really will want something with a quick release head. It isn’t completely impossible to handhold macro shots, but you need either direct sunlight, dedicated macro flashes, or both.
There are cheaper flashes, but, well, there’s a cheaper flash built into the camera. If you’re going to get an external flash, may as well make it worthwhile. I really don’t know much about flashes though.
For Canon, you’d be looking at a Rebel XS w/ 18-55mm IS ($640), either a EF-S 55-250mm IS ($280) or EF 70-300mm IS ($530), and pretty much the same macros which are also available in the Canon mount, though it appears that Canon makes a 50mm macro for $250.
It cannot be overemphasized that all the camera gear in the world will not take quality photographs without a competent photographer tripping the shutter. If money really is an issue, get a Canon S5 for in the vicinity of $400 and take a class. Or get just the dslr kit, no extra lenses or accessories (cept media, battery, cleaning supplies, and bag) and take a class, after which you’ll know better what extra stuff to get.