Here it is the square border! woot =P
ok this gonna take some time, so dont do this if you are short on time ok =P
1. you make a 350x100 pixel document and fill it with white, mark the whole area and copy it ctrl+c
2. make a new document 400x150 with transparent bg and paste ctrl+v
3. the white area should be placed in the middle, now go to layer style and use a black, 1 pixel inner stroke
4. now the cutting begins... choose a corner and then select a 10x10 pixel square, select the move tool and press up on the keyboard about 15-20 times
5. next to it you mark a 9x9 square and move it a way 1 pixel away from it
6. do the same on the other side of it so that you got somthing like this

7. now you continiue this way and you use smaller and smaller all the way down till you get somthing like this

(-Hint- you can place them in curvy shapes to get a more effectfull feeling to it)
8. simply put a bg of your choice on top of the layer with the square border, select the first layer and select the transparent area outside your shape
9. go to the bg layer and press delete then go to layer style and use a 1 pixel inner stroke of any color for the border
10. you are now done and can put text and pics however you like
this is my final result