In 1 and 2, the idea of it being in the future is already expressed by "Tom will come soon" and "As soon as you see your friend".
Additionally, in 1, the wanting is happening now. You already want to have finished the book by the time your friend comes, so the present tense is appropriate.
In 2, if you said "will want to see him", that means that the person is going to tell their friend "Sondra will want to see you [+ timeframe]". What you actually want them to say is "Sondra wants to see you" so when the event actually happens, the present tense will again be appropriate.
I prefer "had spent" in 3 because the spending of the money happened before the returning home.