A couple of good books that will help if you want to understand more about writing for orchestra.
Nikolay Rimsky-Korsakov 'Principles of orchestration.' (The 'bible')
Berlioz, with adittional editing by Richard Strauss.
'Treatise on instrumentation.'
Alfred Blatter. 'Instrumentation and Orchestration.'
There are examples in all three books, and rimsky-korsakov is in fact two books in one with examples from his own work. The Berlioz draws heavily from Wagner, Beethoven, etc. Blatter makes more modern distinctions.
So between the three, you cover a fair chunk of orchestral history and instrumentation technique.