Spa F1 GP

Are there any experts on Spa out there who know the Spa circuit and F1 day arrangements? I am attending for the first time and I was wondering if any of you could help me with some info. Where is the best place to buy well priced tickets? If we sit in the Silver section(rather than grandstands) where is the best place to be on the circiut and what does one do for seating etc? Does one take one's own folding chairs for example as I assume there is no seating in any of the silver sections. Any other info would be also appreciated.