Can this be attached to a Nikon D5000?
If so what sort of adaptor would I need.
Yes it can be attached. There are lots of adapters out there. Fotodiox is one manufacturer that makes a lot of adapters, and there are others. Google is your friend. Make sure you read the small print though, to check that it's an adapter for mounting Minolta lenses onto Nikon cameras, and not the other way round.
But it probably wouldn't be worth doing. Three reasons.
One issue is the incompatibility of flange focal distances. The Nikon F mount is 46.5.mm and the Minolta mount is 44.5mm. That means you could theoretically fit a Nikon lens onto a Minolta camera using an adapter which is 2mm thick, but to do it the other way round, as you want to, the distances don't work. The Minolta lens would have to be mounted further away from the sensor than it is designed for, and that means that either you lose the ability to focus at distance, or you need a corrective optic in the adapter, which of course reduces image quality.
The next reason is that you won't be able to use much of the functionality offered by the lens. You won't be able to autofocus, you won't be able to control the aperture of the lens, you might not get focus confirmation from the camera when focusing manually, and you probably won't be able to meter properly without stopping down the aperture manually (using the camera's depth of field preview control) as part of the process.
The third reason is that the image quality won't be very good. Lens design has come on in huge leaps and bounds in the last 10 years, especially for zoom lenses. Any cheap but modern zoom is likely to offer better image quality than an old zoom.
That's not to say you shouldn't do it. It might be a fun project, learning about stop-down metering and such like. But don't do it thinking that the lens us going to be useful for your general photography.
