Concatenating two PostScript files, and gs whitespace problem

Hi
        I want to concatenate two PS files side by side. I have tried montag
e from ImageMagick but the o/p is very poor and the file generated is very big.
 Could someone suggest some way of doing it with a good o/p quality and reas
onable file size.

        Second question. When I try to "distill" a pdf file from a PS file using
 gs, I get a lot of whitespace around the image which is not present in the PS f
ile to start with. How do I get rid of it (the white space) ?

Thanks,

MS