$0 for me, though it's not because there isn't good OGL stuff out there but, rather, because I'm branching back out into other games. I have to pick up some printed Rolemaster PDFs tommorrow, and I snagged copies of Against the Darkness, Control, Fudge, Lords of Creation, Powers & Perils, and Pie Shop this month (though Fudge is technically OGL, and Pie Shop has an OGC class in it).
There's no $200 - $300 category, which is somewhat unfortunate since I'm probably in that category.
I have a subscription to Pathfinder, that I'll be keeping up. I may pick up one or two of their supplements for the setting as well, and will definately be buying the Pathfinder RPG core rulebook and Bestiary (mostly so I can run the later Adventure Paths without converting, unless the system blows me away).
Other than that, and maybe a Star Wars book or two, I don't envisage buying anything. I already have more game material than I will ever ever use.
(Actually, looking at that the $300 - $500 category might be right for me.)
Zero. I forgot about Star Wars Saga Edition, but even then I'm happy with the core book and the Knights of the Old Republic Campaign Guide for the foreseeable future.
I don't really plan, but I've spent around £20/$30 so far this year I think on just a couple of products*, and I must have spent over £100 last year even not counting miniatures, so I'm guessing $100-$200.
*(1)Expedition to the Ruins of Greyhawk (£12) - my first experience of a WotC adventure path. Seemed very railroady and uninteresting, &
(2) GG's Dreaming Caverns of the Duergar (£8) - looks a like a decent dungeon crawl.
I don't know how much. I've already spent $100 and I'm looking at spending more. Last year I think I spent more on OGL books than any other year a few hundred. Now my group is trying 4e and I have no idea when I'll get back to using my books.
Probably between $100 and $200. I'll pick up Pathfinder at some point, and its bestiary, and whatever their planar book is called. I'll also catch up on some older OGL books I managed to miss (Mutants & Masterminds, some Malhavoc stuff, a few of the later 3.5 books that I never got around to purchasing). Still, nothing major.
I'll likely spend the same amount on WoD products (both old and new).
No planning, but there are a few books I am after still, and which I would like to add to my collection. Nothing I really need, got my bases covered concerning 3.5, but some I would like to have mostly (mostly some WotC 3.5 supplements; very few non-WotC products).