The Naniwa super whetstones are a great starting point if you are new to sharpening being both excellent quality and affordable. Stones work like sandpaper with the higher the grit, the finer the finish. We generally recommend the 800 grit stone for the majority of sharpening work with lower grit stones used for repairs and removing more metal, and higher grit stones used to finish and polish the edge.
All Naniwa Super stones are splash and go. A binding agent unique to Naniwa bonds the material and makes for a more consistent grit size and therefore a more consistent sharpen.
Naniwa Super 220 - A stone perfect for chip repairs and for tools like chisels.
Naniwa Super 800 - The 800 is a great introduction into the sharpening world allowing you to do a lot with one stone. It cuts through material relatively quickly enabling you to put a fresh edge on your knife with little difficulty.
Naniwa Super 2000 - Longer lasting with the stone cutting more smoothly and cleanly.
Naniwa Super 8000 - Perfect to make any knife razor sharp.
Also take a look at the Professional range of stones from Naniwa.