i am a programmer working on ray tracing, i just have one simple scene file that my ray tracer is rendering quite well ... as i mentioned that i am a programmer and a student and NOT a 3d modeller , hence i dont know how to write a scene or scene file, is there any link where i can get some good scenes ...?

i currently use following simple scene for my ray tracer:

Sphere 2.5 -1.5 -17.0 Material 255 255 0 0.5 0.75
Sphere 90 0 4 3 Material 0 128 128 .75 0.45
Sphere 30 2 28 4 Material 111 45 255 .75 0.65
AABB -25 -25 -60 -20 -20 -30 Material 5 250 0 0.5 0.45
AABB -40 -40 -80 -20 -20 -100 Material 89 21 134 0.5 0.9
AABB -30 -30 -70 -10 -10 -50 Material 89 21 134 0.5 0.6
Triangle -2 -2 -7 2 -2 -7 0 2 -7 Material 149 18 141 0.5 0.8
Triangle 9 9 14 9 2 14 3 10 -9 Material 194 108 201 0.5 1.0
Light 48 68 100 25 0 25
Light 14 0 -10 55 45 95
Origin 0 0 14
Target 2 1 -7

can i get some advanced scenes of similar format from some where ??

I don't think most people do vertex coordinate lists like that since the 1980s. Software does that part now. Very few 3D artists would be familiar with that aspect.

But if you open a .obj file with a text editor, you may find similarly formatted coordinate lists. OBJ format is pretty common (if not the most common), so you shouldn't have problems finding models of whatever made in it. Associated materials are referenced in the .mtl file that is normally included with the OBJ.

Outside of .obj, I think Collada and VRML are in plaintext too. (There may be others, but just going with what I'm familiar with. Other formats tend to be proprietary binary stuff or compressed in various ways.)

Of course you're the one with the programming background (which is out of my area of knowledge), so it'll be up to you to figure out how to parse it.

I know it's not much, but I hope that points you in the right direction.

There are a zillion free obj models available on the internet.  Here in the freestuff section you will find many.

You have two threads going.  If we could consolidate that would be great.

I'm glad to make something for you and export in obj.  I use Softimage XSI 2009 (7.5).

I can make something in Hexagon or possibly Carrara 1 (yes, I failed to update), or blender or a bunch of other free apps, but Softimage is my preferred choice.

What would you like?  A modified torus that looks like an engagement ring?  Something really complex like an airplane or a car might involve more points / vertices than you want to manipulate right now.