I like Christopher Hilton's compilation biography of Ayrton Senna from 2004 
I also find his Schumacher biography entertaining, but Senna's life is more dramatic and easier to depict. Both are good reads, nevertheless!
Best Motorsport Books.
The best and most thorough story of the life of Ayrton Senna is Tom Rubython's 'The Life of Ayrton Senna'.
A more intimate story by Ayrton's girlfriend is 'Adrienne - My Life with Ayrton' by Adrienne Galisteau.
'The Death of Ayrton Senna' by Richard Williams is a smaller book but no less superb.
The best and most readable record of 1930's racing is the brilliant 'Silver Arrows' by Chris Nixon.
'Rosemeyer' also written by Chris Nixon is another thoroughly researched standard work on the personable and mercurial German 1930's Auto Union ace.'Mercedes Benz - Grand Prix Racing 1934 - 1955' by George Monkhouse tells the story of the Silver Arrows in beautiful black & white photographs with a lot more inciteful stories besides.'Speed was my Life' was written by the legendary Mercedes team manager Alfred Neubauer and is full of racey stories of pre-war racing.
The two best books on our 'national treasure' Sir Stirling Moss that I have read, are 'All but my Life' by written back in the 60's by Ken Purdy with Stirling's full cooperation and 'Stirling Moss - My Cars, My Career' Stirling Moss with Doug Nye.
The first is a bit psychological & philosophical giving an insite into how our hero approached,enjoyed and survived motor racing. The second more about how he viewed the tools of his trade and their relative merits and shortcomings.
Both 'Challenge me the Race' & 'Champion Year' by Mike Hawthorn are cracking reads recounting a more carefree age when partying were as important as the racing and Mike was brilliant at both.'Mon Ami Mate' again by Chris Nixon, is a dual history of the story of great pals Mike Hawthorn and Peter Collins. A more recently published biography of Mike Hawthorn is 'Mike Hawthorn - The Golden Boy' by Tony Bailey & Paul Skiliter. This is a really thorough story of Mike Hawthorn and with the other three books will tell you all you would ever need to know about Britain's first World Champion.
If you are looking for insights into the people in motor racing then 'The Legendary Years', 'Behind the Scenes' & 'Strictly off the Record' by ex BRM man Louis Stanley will certainly cover the 60's & 70's, and the big man's contribution to safety at this time is much underrated. Two other books on the people involved in various parts of the business are 'Grand Prix People' by Gerald Donaldson and 'Inside Formula One' by the greatest present-day motor racing writer Nigel Roebuck.
If you are into McLaren then 'Teamwork' by Gerald Donaldson tells you all about the people who work behind the scenes in Woking, and 'To Finish First' by ex Team Manager Phil Kerr will give you the full entertaining history of the team.
'A Different Kind of Life' by Sir Frank Williams's wife Virginia is one of the very motor racing best biographies I have ever read. It tells the story of how Virginia met and fell in love with Sir Frank and how they built a winning team. Then it goes on to tell the story of his terrible accident and how they coped with that. A totally brilliant book.
'Winning is Not Enough' by Jackie Stewart is his official biography and tells the story of an incredibly busy and succesful life or rather several busy and successful lives ! He doesn't only stick to motor racing either and it is a big book that you won't be able to put down.
'Life At The Limit' by Graham Hill is a classic story of 60's & 70's motor racing at the highest level, a very entertaining man who seemed to thoroughly enjoy what was to be a tragically short life. 'Jim Clark at the Wheel' by Jim Clark is written in a more modest and self-effacing way which was typical of the man out of the car - but what a tiger in the car ! .
'To Hell and Back' is the story of Niki Lauda's amazing recovery from his traumatic accident - I don't think it could happen today but then how many more men do we have like Niki ?
'Colin Chapman - The Man and his Cars' by written by 'Jabby' Crombac tell the full story of another genius who was a great and inspiring leader and one of F1's greatest ever design innovators.
'Eddie Jordan - An Independant Man - The Autobiography' by Eddie Jordan is like the man vastly entertaining but written with the common touch of a man who is never afraid to say what he means yet you cannot dislike him. Another ripping biography.
If you are looking for the best histories then 'The Complete History of Grand Prix Motor Racing' by Adriano Cimarosti contains so much with maps, signatures, posters etc etc. 'Power and Glory - Volumes 1 & 2' are the standard well-written literary works on the history of motor racing and 'Grand Prix Reqium' also by William Court tells the stories of the drivers who paid with their lives for their love of motor racing.
One of the greatest achievements of recent times has been the private publication of the set of volumes called 'A Record of Grand Prix and Voiturete Racing' by Paul Sheldon. This industrious doctor has done no less than complied a complete historical record of all the top line single-seater racing entry list and results since the sport's inception. These volumes are a complete treasure-trove of information on the sport.
'Time and Two Seats' by Janos Wimfen is a boxed pair of substantial volumes on the record of sports-car & prototype racing. Lots of maps, photos and fascinating statistics. Another standard work.
'Silverstone - 50 Golden Years' published by the BRDC is the story of out favourite airfield and a more modest version published in paperback was 40 Silverstone Years edited by Ray Hutton.
'The Racing 1500's' by David Venables tells the story of 1930's voiturette racing with maps of less well-known circuits and stories of a bye-gone age.
'A Record of Motor Racing 1894 - 1908' by Gerald Rose is history for the very early days when endurance was a important factor than speed. Still the very best on this period and the standard work.
The remaining books in my personal list are ones perhaps that are less easy top group. 'The Science of Safety' by David Tremaine is the story of how motor racing was gradually forced to come to terms with safety. Each horific accident produced a reaction which gradually helped to reduce the death-rate. It is an absolutely fascinatingly evolving story.
'The Racing Driver' by Dennis Jenkinson is the classic treatise on what is required and is written by the greatest motor sport writer of his day.'Formula One - The Cars and Drivers' by Michael Turner & Nigel Roebuck tells the stories of great motor races using the paintings of Britain's greatest motorsport artist Michael Turner.Nigel Roebuck tells the stories behind the paintings, often using insightful driver quotes and recordings.
A recently published book is 'Classic Motorsport Routes' by Richard Meaden who illustrates and maps classic roads such as the Col De Turini and the Targa Florio that you find and then drive yourself. However your better-half may not be quite as keen ! The last book I would recommend for the serious motor sport book collector is 'The Constant Search' by Charles Mortimer. This is a collectors search list with little reviews of all the significant books up to the 80's rarity-values and as much detail as you could possibly want.
There's a good few 
None of these are overly long--each is about 250 pages--but they're all worth the time, in my opinion.
