This is the right section, fear not
For instrument ranges etc I recommend wikipedia. It should have the ranges of any instrument you choose to work with as well as common techniques and other useful information. As for learning how to write for them, I can strongly recommend the Orchestration masterclasses on this forum, in the masterclasses section. They are written by one of our most knowledgable members, QcCowboy, who has a real talent for teaching as well as being an amazingly talented composer.
If you want a brass section I can tell you the norm would be three trumpets, four horns, two tenor trombones, a bass trombone and a tuba. This could, however, be cut down if necessary.
Good luck
