`psutils' is a great Postscript utility package that I used (and compiled) when I was using my Amiga. I was hoping to concatenate (join together) several PDF files. I used `pdftops' to convert the files to Postscript. Incidentally, the output of pdftops is far better than pdf2ps, particularly if there are large graphics. Unfortunately, `psmerge' has been broken since 1995. `man psmerge' suggests using gs (ghostscript), but that produces a very large and rather craggy bitmap file.
Will Henney in comp.text.tex has a very Linux, but also slightly awkward solution (July 19, 2003). Use pdflatex...
\usepackage{pdfpages}
\begin{document}
\includepdfset{pages=-}
\includepdf{doc-a.pdf}
\includepdf{doc-b.pdf}
\includepdf{doc-c.pdf}
\includepdf{doc-d.pdf}
\end{document}