Book

[Aesop55]

I am looking for a good textbook. especially for a beginner. I just need to attach pdf files and scale to size and print.

[pendean]

IMAGEATTACH is the first command.
SCALE is the second command: since PDFs are paper scales (assuming your PDF is an actual scaled document), AutoCAD is real-wrold scales, so you'll have to do the math in your head first.
PLOT is the last command you wish to use.

All three explained in HELP in LT.

Here are some very basic blogs on the topic:
http://www.ellenfinkelstein.com/acadblog/attach-a-pdf-as-an-underlay/
http://www.cadalyst.com/cad/autocad/bringing-pdfs-autocad-12946

[gccdesign]

As far as scaling a PDF image in model space goes, here is what I do. Assuming it is a PDF that has some known dimensions.

Draw a line in model space that is the length of a known dimension in the PDF. Rotate the line or the PDF to align with each other. Preferably horizontal or vertical.

Using the Rotate command with the "R" reference method is great for this.

Position your line at the start point of the known distance on the PDF.

Use the Scale command with the "R" reference method to scale the PDF to match the line.

Voila, you have the PDF at approximately the correct scale in your model space. No calculator or brain math needed (whew!).

GChapp