Fortunately, there's a vast difference in quality when starting with a $500 budget versus a $1,000 budget. I'm going to limit my recommendations to Canon, since that's the platform I'm most familiar with. Prices in US dollars.
Adobe Creative Cloud subscription: $20/month, or $240/year. This gets you Photoshop, the industry's most popular editing software, and Lightroom, a processing and cataloging application. Cost is $240 a year, charged monthly.
Used Canon 50D: Around $380 through B&H photo. Probably less through KEH Photo or your local camera store. This is a tough, capable camera which quite a few people are still using in fairly demanding applications. 15 megapixels gives you enough room to crop (cut off the image's edges to focus the viewer on different areas) if you're trying macro work without a dedicated lens. The 10 megapixel 40D is about $100 less, but 10 megapixels is a little on the low side these days. Still workable if you want to save some money.
Tamron 17-50mm f2.8 XR Di II LD: $500 new. With a wide f2.8 aperture, this lens will probably be with you a while. One of the biggest problems with basic kit lenses is that they have tight apertures, which can limit you to shooting well-lit subjects with fairly deep depth of field (not always desirable). This one's basically a premium kit lens, and it avoids that problem.
Total out of pocket for the first year: $1,120 ($880 on gear, $240 month-to-month on Photoshop).
Personally, I strongly advocate getting one camera and one lens to start, learn that combination until you know it inside-out and backwards, and build your post-processing (Photoshop/Lightroom) skills at the same time. Once your camera-handling abilities reach a certain level, post-processing skills are required. Nothing fancy like compositing or HDR is necessary, but mastering color correction, sharpening, dodging, and burning (all of which we can explain later :D) can take your work to a remarkably professional level. Just don't expect this to happen overnight, or even inside a year. Learning this stuff takes practice, persistence, and sheer pig-headedness.