Macro doesn’t have to be expensive. And you don’t need a special lens for it if you just want to play around and experiment. Use what ever lens you have—a kit zoom lens is fine. Just figure out what lens mount your camera uses, and the filter diameter of the lens you plan to use.
By using a lens reversal adapter, you can put your camera lens on backwards, which allows you to get your camera very very close to your subject, (typically between 1-10cm). This allows you to achieve magnification like the photos in this album.
A typical set up using stuff people already have would be a Canon Rebel with the 18-55 kit lens. This is an EF mount lens, with a 58mm thread, so you just need to look for a 58mm EF lens reversal adapter on eBay, order one, and then wait a month for it to show up.
These adapters can be found to combine almost any old or modern lens with any current lens mount (micro-four-thirds, aps-c, full-frame, etc).
These photos were taken on a Fuji X-E2 with its kit lens, and were sharpened in Lightroom, so your sharpness may vary, but you should get something acceptable considering the adapters can be as cheap as $2 with free shipping!!!