Scan and send a signed contract as PDF

After signing the contract, you scan the pages, and each of them will come to you as jpeg (or some other format) image file.

Then, print to pdf each of these images. Now, you have a bunch of PDF files.

If you have ubuntu, then you can merge the pdf files into one, using these instructions:

http://ubuntuhowtos.com/howtos/merge_pdf_files

First of all you will need the program called pdftk. You can get it by opening terminal and typing:

sudo apt-get install pdftk

Now you can merge pdf files by putting them in the same directory and typing:

pdftk 1.pdf 2.pdf 3.pdf cat output merged.pdf

or if you wish to merge files in alphabetical order you can simply type:

pdftk *.pdf cat output merged.pdf

If you use this last command, make sure you don't have any other files there in pdf format which you don't want to be merged with your contract (or any other document, of course).