There are many, many, many options.
Want something that'll do everything all the time?
Get a SB-910. It's got power to spare. It works perfect with your camera all the time. It can command slave flashes. It might even have a can opener. Maybe the kitchen sink too. BUT it's $550!
The step down, the SB-700, cuts out a lot of stuff. It's at least 20% less powerful. It can command slaves though. And it works perfect with your camera all the time. It's $350.
Now, if you can cut out some of the features, and deal with a couple short comings, older Nikon flashes are fantastic.
The SB-24, SB-25, SB-26, SB-28, SB-80, and SB-800 are fantastic. All were akin to the $550 SB-910 in their time. The SB-800 should work great with your camera. The SB-28 and SB-80 will only work on auto mode - which before 2004, was the only way most cameras worked anyway.
The SB-800 (which the SB-900 and SB-910 replaced, so it's very recent) still goes for $250-300 - and it's a far better flash than the SB-700.
The SB-80 (which was the flagship flash the SB-800 replaced) goes for about $100-150
The SB-28 (flagship before the SB-80), $75-100
SB-26 (flagship pre-SB-28), SB-25 (pre-SB-26), and the SB-24 (pre-SB-25) go in the $50-75 range.
You could do much of what you want with a SB-24 to SB-26, or SB-28 if you stumble across a deal.
Over the last 3 years, I've bought a SB-24 for $50 and a SB-25 for $36. I have a few more that I've bought over the years, but I haven't paid over $100 for a flash.
Here's a write up on a SB-24:
Strobist: Steal This Flash - The Nikon SB-24
Here's the SB-26:
Strobist: For a Few Dollars More: The Nikon SB-26
Here's the SB-28dx. It's more about the nitty-gritty info about the flash rather than using it for off camera operations:
TTL Flash Photography with Nikon F5 - SB-28DX
mir.com.my also has a wealth of information to spend time going through to compare what should and what won't work from the back catalog of Nikon stuff.