My friend David Tsnen from Urban Sketchers Singapore has released his sketchbook Start Sketching Start Drawing recently. It's a 178-page paperback that collects sketches he has drawn over the years and also his thoughts and tips on drawings.
The sketches are split into different subject matter, such as urban sketching, landscape, zen stuff, abstract, mountains, trees, and other nature subjects. His style reminds me of the Chinese style of drawings. He likes to use brief lines, brushes and ink washes. One characteristic of Chinese style paintings is sometimes it's difficult to understand the perspective, for example you can't find the vanishing point. I enjoy looking through the book. It's interesting to see the style from people because it's like an extension of themselves.
The last few pages of the books feature some helpful sketching tips.
The book's published by Basheer Graphic Books and you can find it at their store and probably other bookstores in Singapore.