Vasant Lad's second textbook on Ayurveda gives a good overview on diagnosis and assessing doshic imbalances, with some great illustrations and charts. In many respects a fantastic textbook - well written and clear.
My only problem was that many times I found myself wishing he'd explain things in more depth. Lad often throws in diagnostics as he's explaining a concept, and then doesn't list them in one place to review, which makes it hard to remember where you found that nugget of info.
All in all a very good textbook on Ayurveda - a good reference for practitioners or lay people like me who are interested in the concepts of perfect health.