Hi Prateek,
Tools:
1. Wacom Digital Tablet (or any other brand. iBall has come up with their series which is cheap and works good. I've one at my work place for quick sketches. Wacom is the best out there).
2. Photoshop (this is one expensive piece of software) is used by professionals. You may want to try out freeware like GIMP, Artweaver, Pixia etc. I personally prefer GIMP. Artweaver is similar to Corel Painter with natural media painting experience. If you are looking at printing the comics, then go for Photoshop. It has support for CMYK. With GIMP you may need additional plugins which are not on par with Photoshop.
Lots of tutorials on the internet shows you how to do digital coloring, shading, half-toning, tone halving, throat gargling et. al :)
cheers.
simianart.com--
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