In reply to abr1966:
As already mentioned auto extension tubes are the cheapest way to get into macro, using your existing lenses.
But if you want a more dedicated macro lens, you won't go far wrong with a (manual focusing) Laowa 100mm f2.8, which goes all the way to 2:1 magnification. Also good as an ordinary short telephoto.
I'm after a Laowa macro lens myself, but for Fuji X mount.
From what I've seen in the reviews it is produces extremely sharp punchy images, even at 2:1. It is apochromatic, so no colour fringing. Depth of field is wafer thin 2:1 at f2.8, so it would need to be stopped down (preferably mounted on a tripod) - or you could focus stack multiple images in post.
Laowa is Chinese, but don't let that put you off because it is very well put together, the barrel being all-metal construction. £469 new at Wex, which is less than a third of the price of the Canon 100mm equivalent - and with better image quality.
Post edited at 13:28