Thanks guys. As for the programs used, I started with an initial sketch using PaintChat (a free Java application, which kind of resembles something between MS Paint and Adobe Photoshop), and finished it off a bit more in Photoshop. I'm happy with any application that comes with opacity-setting brushes and good color pickers.

Some kind of digital tablet is not necessary, but it's nice to have. The Wacom Intuos series are great if you can afford them. The tablets don't truly give you the feel of a real pen/pencil, but it's pretty close.

My personal favourite applications for digital painting are:

• Adobe Photoshop
  
  Photoshop has a very nice brush system (easy to make custom brushes if you want to), and it has a great feel to painting in it. The differences between Photoshop CS2 and the former Photoshop CS are insignificant for anyone who uses the software for drawing/painting applications. I do believe CS2 has some kind of perspective guide tool, but I haven't tried it yet.
  
  http://www.adobe.com/products/photoshop/main.html
  
  
• Corel Painter IX
  
  The latest version of Painter comes with a large selection of brushes intended to simulate traditional painting. The program can emulate traditional tools fairly well, but it's far from perfect. However, the sheer quantity of tools, many of which are extremely good, makes the program very interesting, and can be used really well in conjunction with Photoshop. Even if you're normally not into (digital) art, go ahead and download the 30-day, full-functionality trial of the program. It might very well get you interested in the field of art, or at least give you a fun time trying out lots of different art mediums without creating a mess of oil stains.
  
  http://www.corel.com/painterix/home/
  
  
• PaintChat
  
  PaintChat is a free Java-based drawing/painting application, which can pretty much be used on all computers with any graphical interface OS. While it is one of the most powerful pure-bred art applications, it also comes with the very neat possibility of partaking in simultaneous multi-user sessions who share one large canvas. It is, unfortunately, not very easy to run without some basic knowledge of Java applets. Some knowledge of the Japanese language is helpful for installing the application, although not necessary by any means.
  
  http://hp.vector.co.jp/authors/VA016.../download.html
  
  
• ArtRage
  
  Just like PaintChat, ArtRage is a free application, with the best oil paint simulation engine to date. If you're not the type of person who knows exactly what you want to achieve when you start painting, ArtRage may provide the same kind of difficulty as real oils; the fact that it's very hard to overpaint wet paints without blending the colors into some weird hodgepoke.
  
  http://www.ambientdesign.com/artrage.html

Hmm, did I forget any? openCanvas perhaps, which is a pretty cool multi-user "Photoshopesque" application, but I don't use it very often.

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