Greyscale maps and illustrations are still important because colour incurs an additional cost in printing and is most effective on a glossy paper which poses problems for collation in automated and print-on-demand services. Therefore, it is rare for books to have more than a few colour plates. It is not so much an issue of technology, rather it is predominantly one of price. This is confirmed by a quick straw poll of a dozen of the technical and GIS books on my shelf. The exception would be an atlas and the additional costs of colour printing are usually reflected in the price of the book.
Greyscale base-mapping can also play a very important part in cartography where you need to overlay a semi-transparent colour raster. This is something I do on a very regular basis for wind farm visibility analysis for instance. The raster overlay will represent the number of turbines which a visible at a given location and this is most sensibly represented by a colour scale (especially where you have many turbines rather than just one). To overlay a colour raster on a colour base-map results in a final map which can be very difficult to read and, because of colour mixing between the base-map and the overlay, the key can even appear incorrect.
Greyscale illustrations (as opposed to maps) can even sometimes be easier to understand and are therefore, in such situations are better left without colour. This is often the case with technical drawings.
I'm not clear what you mean by 'elaborate grey scale maps and illustrations'. If you mean make complex maps and illustrations, of course it is still possible as we have not lost any technology, we have merely gained improvements in printing in general and colour in particular. Though there would be significant cost implications to go really old-school and have hand engraved plates made from which to print your map!
Should you print in black and white? Well, it depends what is appropriate and aesthetic. Colour can make the task cartographic representation easier for the cartographer but does not necessarily result in a more informative/beautiful map. Also the bean counters may veto the use of colour on 75% of the maps and illustration with which you had hoped to embellish your magnum opus, so you might be forced to use greyscale even if you wanted to use colour and that will probably mean you'll have to redo the cartography. All I would say is you will probably do 90% of your maps an illustrations in colour, but should be prepared recreate images in greyscale if/when required.
I can't give you a link to a tutorial but pattern fills can really come into their own in a greyscale map instead of colour. Of course, you get the same issues of aesthetics and the potential to confuse rather than edify with patterns as with colour. However, you could do worse than trawl this site. Here is a discussion on cartography for colour blind people.