I picked up a very nice, low-mileage D200 for my son as a holiday gift to replace the D40 I gave him a couple of years ago
I want to find a lens to go with it.
It will most likely remain his one and only lens, so I'm thinking a zoom like an 18-200; 18-135; 24-120
My budget is under $200 for something in 9.5/10 condition
I'ver never owned any of these lenses, so I need some help
Still having and rarely using my D200/18-200 combo, I really miss the 18-70 I originally had for it. It's a much better lens if you can live without the extra reach. I'm pretty sure you can pick up the 18-70 for cheap, probably under $200 if you look hard enough.
My vote goes for the 18-70 for $120-$150 used or Tamron 17-50 2.8 for a little bit more than $200 but you'll get an amazing lens. As ckcarr mentioned 18-200 is almost double your budget and it's not better than the ones above.
What's he shooting with on the D40 right now? The 18-70 is a really nice lens, but there's none available at the moment through KEH, but I plugged $225 in as a filter and came up with a few lenses within, and just a bit above your budget, depending on what he's shooting now
Take a look at the 18-105 at Cameta refurbished, year warranty. VR would be helpful on the D200 and its a nice working range. $220 plus free shipping, I've bought from them for refurbished and the stuff I got was in new shape. At little over your bugdget but not by much.