This video cleared up a lot of confusion for me. I've had some small success in finding lost tech 2 drones, which are worth about 500K ISK a piece. I have been using d-scan to locate the probes' direction and distance in the regular view, then switching to the solar system map to try and place my probes in the right area so I can scan them down and be able to bookmark them so I can warp there and claim my prize.
But the last few times I've tried, the probes have been alone in the view, with no celestial objects for me to align to. And with no indication of what direction I'm facing (up or down, I mean), its been a frustrating failure.
However, with this video I now know that I can d-scan from the solar system map view. Obviously this video is intended for people who want to use the probes for combat and he takes a lot of steps to minimize how long the probes are close to the target. That's not a factor for me, so hopefully my searching will get easier now.
Next day update: this works a treat! Last night I picked up about 10 Hobgoblin IIs, 2 Hammerhead IIs and a Warden II (sentry drone) in about two hours. As I keep practicing, and get better scanning skills, I think this will speed up.