reeferaddict was stating a good point earlier about IS not helping with fast moving objects.
If you're on a budget, you can go for a good non-IS lense, and put that investment into a good tripod and a monopod. You MUST have those handy for lots of shots, and I'd choose a tripod/monopod over an IS lense. I love my monopod. Special ordered the Manfrotto 680B (monopod 16" when compacted), and the #234 rotating head. I take it out with my whenever I go out photographing. No need for an IS system
I also use the wired remote, so I can just hold the monopod steady, and my pressing of the button doesn't cause any motion blur.
and I don't think ANY is lense would handle touchy macro shots well, especially if you get into adding extension tubes and other stuff. A tripod can't really screw up (unless you have a cheap head. then it sucks)
and the tripod/mono pod are investments you probably will NEVER bother upgrading, but will get LOTS of use from. Stay away from ball heads if you want something long lasting, and just remember to tighten till it's just snug. Overtightening shortens the life of your head.
Once you've been photographing for a while, you can then decide on what to spend your money on for specialty lenses. Just like how reefaddict first bought a rebel, then upgraded to a 20D based on his own experience he got from using the Rebel. (and how I bought a digitel rebel, then a film Elan, and now I'm thinking of going pro-medium format Hasselblad. Film vs. gear *grins*). I think he also said he never had a "real" macro lense. Me neither, as I use extension tubes, and I'm contemplating a bellows system, as I might be able to get one for a great deal.
I myself like straight, non-zoom lenses, but that's my tastes
Oh, and for low light photography, go film
Supplement your digital with a film body. The body won't cost more than $250 new anyways, with today's film body prices. And a profesional film processing center can develop your film, and scan it for you on a great machine, giving you like a 20 megapixel or higher image in most cases. You can get some nice high speed film, and you can even pull it down a bit and get amazing photographs out of it for low light.
And buy a Holga! lmao. you'll love it hehe (can you tell i'm an art student? lmao)
oh and I've started building a 4x5 view camera for macro photography. I can give anyone plans for it once I'm finished if they're interested. It'll be a multi-lense system, not costing me more than $100 to build. Getting the glass from an optical surplus. 200 megapixels of film, baby, yeah!