Merging PDF files needn’t be expensive
How do I … merge two or more Adobe (pdf) files into one?
?
If you want the high-priced option, go to the Adobe Web site and buy the $300 version of Acrobat.
If not, find the best, cheapest online tool to get the same result.
That would be either CombinePDFs, if you use a Mac, or PDFill PDF Tools, if you use Windows.
Both are freeware, with the option of making donations to the publisher.
For the Mac version the download is at http://monkeybreadsoftware.de/Freeware/CombinePDFs.shtml.
The PDF Tools version is at http://pdfill.com/pdf_tools_free.html.