PDFTK Builder - PDFTK Builder is a free graphical interface to for PDFTK, making it much easier to use.
PDFedit - Free (and open source) editor for manipulating PDF documents. GUI version + commandline interface.
QPDF - QPDF is a command-line program that does structural, content-preserving transformations on PDF...
Adobe Acrobat DC - Make your job easier with Adobe Acrobat DC, the trusted PDF creator. Use Acrobat to convert, edit and sign PDF files at your desk or on the go.
iSafePDF - iSafePDF is a free open source PDF protection software.
Master PDF Editor - Master PDF Editor is complete solution for editing PDF and XPS files.