Nathan, just one remark on buying a speed-light. If it's not a big step-up in power just get along with the built-in flash. Your D40 has superior high-ISO capabilities, and that gives the camera-flash a great advantage.
And the idea of having a stabilized lens like the Nikkor VR 55-200mm is that you can do available light shooting. No need for an additional flash there.
if you later on really need an extra flash, go for the more powerful, like SB-600/800, that can be used as slaves to the onboard flash. That way you get real value for your money...
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Thomas (beware: Nikon-fanboy and moderator!)
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