I've found over the years that no one makes a better bag than Crumpler at any price. Getting one for free only makes it sweeter.

I'm using a 5 Million Dollar Home for my D300 which isn't too dissimilar from the Pretty Boy series (the former seem to be North American designs while the latter only are only available in Europe - odd for an Australian company).

I actually have a LowePro Slingshot 200 I want to get rid of. It's constructed reasonably well and holds enough gear, but it just wasn't my cup of tea.

Take a look at Tom Hogan's site for some useful information on all sorts of Nikon and general photography topics. Stay away from the forums at DPReview.com - 95% of everything there is noise.

I second the high marks for the RRS (Really Right Stuff) ball heads, clamps and brackets. Can't recommend tripods from Induro - I snapped the top tube on mine during vacation in Portugal. Luckily no damage to the camera. At the high end of the spectrum (and unfortunately price), Gitzo makes arguably the best tripods and monopods in the business. Manfrotto stuff is also very nice (they're owned by the same parent company now), but uses lever clamps instead of twist-style.

A new (shoulder) strap is high on my recommendations list. Something with quick release capability and clips that can be rotated freely without twisting up the strap. The Domke gripper is a no-nonsense simple strap that does what it's supposed to do. Added bonus is that you're not advertising to the world (including would-be thieves) that you're using a Nikon camera.