I have to start making up and edit some site plans at work, I have recently been using the trial version of AutoCAD LT2012 but I only have about 8 days left on it. Although my company is loathed to pay for a full version for me as it doesn't really warrant it for the amount I'll use the program. So I am on the hunt for a CAD program that can be used in a commercial environment for free, I have tried DraftSight and it's pretty good but it really hammers my CPU on my work PC. (Using 60% usage for moving the mouse on a blank screen, never had problems with AutoCAD tho) It'll also need .DWG support so I can send things to head office to get plotted. (The engineering manager has AutoCAD) Thanks in advance.
Scketchup ? It's not a feature-full software but I think it'll do the job for site plans. Plus the PRO version of SU has a DXF / DWG export tool and it costs only €360. http://sketchup.google.com/intl/fr/product/gsup.html Blender is a nice free tools too, but more suited for organic modeling.
i don't know about the price but you might be able to get a used autocad license for an older version (not older than '06 i beg of you) instead of buying a new a cd with the value of a rather good used car.
I'm using Sketchup Pro as I needed .DWG support, however, check any .DWG files before importing into sketchup as some items will be ignored.