Hinduism is not based on one single text book. Though it could be said that Vedas are the base, in essence veda is nothing but knowledge. It is the science of the self and Supreme. The science can not be limited to one book so is Hinduism. If you are looking for a source where all the principles are given, then there are three texts. They are called "Prasthana Traya" — the principal three. They all present the same truth.
The first is the Upanisads. These are parts of the Vedas. There are innumerable Upanisads. Ten of them were chosen by Sri Sankara, a great saint and philosopher, as to contain the ideas in all the Upanisads put together. This forms the first principal text. These are unadultered, raw, first-hand observations of spiritual phenomenon. They do not try to propose a model to fit the observations. The observers have not imposed their ideas or even tried to classify the observations.
The second is the Brahma Sutras. This was authored by Veda Vyasa, who masterminded the current organization of the Vedas and the same person who authored other great works like Mahabharata and Bhagavata. Brahma Sutras present the concept in the Upanishads in a logical and highly technical manner. It is a scholarly work which establishes the concepts in the Upanishads on a strong logical foundation.
The third is the Bhagavad Gita. This is a record of the conversation between Sri Krishna and Arjuna. This text talks about the practical application of the concepts in the Upanisads to everyday life. It is said in one of the scriptures, "If the Upanishads can be considered as cows, the Bhagavad Gita can be considered as milk." Truly, the Gita is the essence of the Vedas. It is a part of the Mahabharata. The Bhagavad Gita consists of 18 chapters and about 700 verses. It deals in depth with all Yogas or ways of God-Realization. The Bhagavad Gita never commands one what to do, instead it gives the pros and cons of every issue and the final decision is left to oneself.
Thus these three texts present the Hindu philosophy and religion in a scientific and practical manner as — observation, modelling and application.
Hindu texts are typically seen to revolve around many levels of reading, namely gross/physical, subtle and supramental. This allows for many levels of understanding as well, implying that the truth of the texts can only be realized with the spiritual advancement of the reader.