I am very much impressed by the "inset" like effect in many latest websites. Some examples are alt text http://img687.imageshack.us/img687/457/inset2.png
and
alt text http://img163.imageshack.us/img163/8158/inset1.png
The line in the center. Nowadays, many websites use these kinds of lines/effects.
I tried to achieve the same with borders but the color combination is not working me and it is not proper.
Do other websites use images for these ? is it easy to this ?
Any example css ?
Example sites: http://woothemes.com, http://net.tutsplus.com/ , http://www.w3schools.com (in the header) and in wordpress admin page sidebar
Don't know if this will help, but using 1 px borders that are slightly lighter and darker than the background of 2 adjacent elements can emulate this. For Example:
EDIT:
As a side note, switching light and dark in the example above will give you a slightly raised/embossed border effect.
Simply do the following:
Play with opacity and colors to suit your design, It works on all backgrounds I think ;)