I was planning on just buying some cheapo hold-me-over lens but I splurged with money I don't have. I bought the Nikon Nikkor 80-200 AF ED. I got it used for a great price and I think I'll be happy with it. I plan to shoot a little children sport photography, so I imagine it will work just fine!
Tom's admonition is very appropriate. When you see the kind of results that badass baby will give you, it will be hard to use a "consumer grade" lens again... luckily, there are (some) bargains to be had.
IMO, you did exactly the right thing, buying used and one generation back, you got a mighty fine lens, for I'd guess a lot less than current-generation new.
I did the same and got the same lens one generation older than yours and it totally kicks ass!!!
I have dropped a ton of cash on different lenses and am not happy with any of them until I got this one.
I now want a wide zoom like maybe the 18-55 f/2.8...saving my pennies
Don't worry your neck muscles will soon build up and you wont even notice your wearing it untill some envious other photographer starts staring at it..........