I've just gone 'up' to a full frame camera, the D610. Now I have to buy all new lenses. Which would be the nearest to my old 18-105mm that I had on my cropped D7000?
Do the crop math backwards. :) You went from a 1.5x crop sensor to a 1x crop sensor, so if you multiply the focal lengths for crop by 1.5, you'll get the equivalent FoV full-frame focal lengths.
18 x 1.5 = 27
105 x 1.5 = 157.5
So any lens that covers 27-157.5 (or an equivalent) will be able to fulfill pretty much the same purpose. So, in the current Nikon lens lineup, the 28-300 superzoom (which is sort of the FX equivalent of an 18-200), or 24-120 would probably be your closest equivalents.