A lot of fanartists don't really know where to start with CG art, so here's a step-by-step tutorial I made while colouring in one of my own pictures... It's for Photoshop 6, but it'll work for Paintshop Pro too.

Start with the scanned, greyscale lineart. It often helps to adjust the brightness/contrast and gamma correction of pictures before starting to get the lines how you want them.

Next paste the lineart onto a new layer, and set the blend mode to 'multiply'. This bascially makes all colour put on layers below it 'add' to the black lines. Then add another layer beneath the lineart layer to put the colour on.

So when you add colour to the 'colour' layer, the colour will 'go under' the black lines, like in the picture on the right.

Continuing on, you can colour the rest of the picture in base colours. If you know how to use layers, then it can help to use more than one layer. I usually use about three. The benefit of doing this is you don't have to worry about going over the lines in areas which are coloured on layers above. But like I said, if you're not used to them then stick to using one, for simplicity's sake.

When you colour, it's a little easier in the long run if you use the polygonal lasso to select areas and the paint bucket to fill them. That way you don't have to continuously change brush sizes. Here's the pic with the base colours in place.

Go to Cel Style Shading --->