Can you fit a sigma fit lens onto a nikon f mount camer. i have some great lenses on my old sd 10 but have gone over to nikon cameras

That depends on the lens. Sigma makes their lenses with a variety of mounts. If the lens has a Nikon mount then you don't need an adapter at all.

Since the Nikon lens mount has a deeper flange depth than other mounts, you cannot fit a lens with another mount onto a Nikon body without losing the ability to focus to infinity. Because of this, you won't find an adapter for another mount. Adapters are available to fit Nikon lenses onto other cameras but not the other way around.

Sorry, no. If it fit onto a Pentax camera then the lens has a Pentax mount. The Nikon (I assume you mean the D80 digital camera, or perhaps the N80 film camera) has a Nikon mount. Since the Nikon mount has a deeper flange distance than the Pentax mount, there are no adapters available to allow you to fit a Pentax-mount lens onto a Nikon camera.

Sigma makes their lenses with a variety of mounts for a variety of cameras. A lens with a Canon mount, for example, will not fit onto a Nikon camera. Assuming the lens has a Nikon mount, it is fully compatible with the D200.

If you mean the 150-500mm, you can see a review at
http://www.popphoto.com/gear/2008/12/sigma-150-500mm-f5-63-dg-os-hsm-apo-af

In general, Sigma supertelephoto zooms have a pretty good reputation. However, only YOU can decide whether a particular lens is "good enough" for you.

Sigma makes lenses with a variety of mounts to fit a variety of cameras. A lens with a Canon mount won't fit onto a Nikon camera, for example. Assuming the lens has the proper mount for your camera, it should fit fine.

Assuming you get one with a Nikon mount, yes. Sigma makes their lenses with a variety of mounts to fit different makes of cameras. A lens with a Canon mount, for example, will not fit on a Nikon. A lens with a Nikon mount is fully compatible with the D50.

It depends on the lens mount. Sigma makes varieties of their lenses for different camera mounts. A lens with a Canon mount will be compatible with any current Canon camera. A lens with a Nikon mount will be compatible with a Nikon camera. Any one lens can fit one but not the other.

Assuming the lens has a Nikon mount, then it will fit and work on the D60. Sigma makes lenses for a variety of cameras; a lens with a Canon mount, for example, will not fit onto a Nikon camera. However, the 70-210 is a rather old lens. Unless it specifies "HSM" it will not autofocus on the D60. The D60 does not have an autofocus motor, relying on the lens to have one. Nikon calls such lenses "AF-S" while Sigma designates theirs "HSM".

Yes, assuming you get the Sigma with a Canon mount. The D30 has the Canon EF mount like other Canons. Sigma makes lenses with a variety of mounts, and a lens with a Nikon mount, for example, will not fit onto a Canon.

Assuming the Sigma has a Nikon mount, yes. Sigma makes lenses for a variety of cameras, and each camera maker has its own mount. A lens intended for a Canon camera, for example, will not fit onto a Nikon camera.

Assuming the lens has a Nikon mount, yes.

Sigma makes lenses for a variety of cameras. Different manufacturers use different lens mounts, and they are not interoperable. A lens with a Canon mount will not fit onto a Nikon body, for example.