I have a Meade Refracting Telescope and I have a Nikon D-50 camera.
I would love to take pictures of Moon, etc as seen in my telescope using my camera.
What is the best way to do that?
There's a few different ways to do this. It sounds like you're most interested in afocal or prime focus methods though.
Afocal photography is putting the camera up to the eyepiece and taking a picture through the eyepiece. The advantage here is that you get the magnification of the eyepiece, but you lose some quality due to the extra glass the eye piece imparts.
Prime focus photography is where you'll take the eyepiece out and attach the camera with a t ring adapter and a camera to telescope adapter. The second is basically a eyepiece that a generic t ring thread screws on. The t ring is a standard thread on one side and a special F mount (for you) on the other side. Prime focus methods won't get you super high magnifications, but will get you clearer pictures.
There's one problem you'll have with both of these. The earth is moving. Yup, spinning around and around. And while the sky doesn't look like its moving fast, when you try to take a largely magnified picture of it, it is. To get reasonable pictures with astrophotography you either need to do a much larger field of view than going through your telescope - or get tracking for your telescope/camera.
It's been 20 years since I owned a telescope, but what I used was a Nikon T-NF adapter. I believe you'll find these if you search for T-ring or T-adapter. It is a narrow glass-less adapter with a nikon mount on one side, and threads on the other. Mine seems to be 42mm, which is probably a standard size, but you'll want to make sure it fits your telescope before you purchase one.
Amazon has a Meade #64ST T-Adapter and B&H Photo have a Meade T-Mount SLR Camera Adapter for Nikon F-Mount
There are no doubt others here who are actively doing astrophotography, so I'll leave it to them to answer you more completely.
I also have a telescope, when I bought it I was a really noob at photography so I had only a point and shoot and in order to take pictures of the moon what I bought was an adapter that could hold the camera against the lens of the telescope. Examples here: Moon 1, Moon 2.
I've recently looked into this matter more seriously and the solution that I found is to buy a piece called "T-adapter", so instead of putting a lens into the telescope one fits this adapter, which should be attached to the camera as a lens.