I found this book to be slightly less than useful when I began graphics programming. Some of the programming techniques employed are not very good. for instance, instead of scan-line converting a polygon (fast) to fill in polygons, he uses a flood fill (SLOW)
However, as I moved into higher resolution modes I found the tables dealing with VESA modes and DOS subroutines, etc. to be an invaluable resource.
For the excellent reference material on VESA, it deserves 3 stars. However, if you are a beginner I recommend a book by Andre LaMothe for graphics.