Pdf printer substitute?

I use AutoCAD to make large scale (24" x 36") construction document sheets. The only printer I have is a standard letter printer, but planned on using a pdf printer to define large scale sheets in AutoCAD even though I can not print them at home (I send pdf's to a print shop with a plotter). I bought Adobe Acrobate Pro; How do I install a pdf printer (or something similar) on my OS X computer? With no driver I am limited to sheet sizes of my home printer. What can I do?