A great tool for dealing with pdfs is pdftk. It is a toolbox of the command line, which is able to split, merge, rotate, password-protect, change metadata, apply background and some more. I use it in combination with latex, which gives me some nice pdfs, which i want to merge in various ways. There is a way of including pdfs right into latex, but that’s not something latex is really good at. I also used it to split a serial letter longer than a page. I was able to print the serial letter of Microsoft Word just in one large pdf where all letters were included and with a script of pdftk i could cut them in separated files. pdftk is open source and available for Windows and Linux also Mac.
merge pdfs in the sequence they appear
pdftk a.pdf b.pdf c.pdf cat output abc.pdf
the command for splitting some sites is
pdftk input.pdf cat 1-4 output pages_1-4.pdf
see the excellent man page for more!
PDF version and embedded fonts
If you need information about the PDF version or the embedded fonts in a .pdf file, you can use the commands pdfinfo and pdffontsrespectively. Information pdftk’s dump_data does not provide at the moment. Both are part of xpdf.