I have used variants of Accelrys Draw, and they are very good. There is a free-for-academics/students version (http://accelrys.com/products/informatics/cheminformatics/draw/index.html) which works for everything I've needed. I've used the outputs for publications without any questions.
You can go for ACD ChemSketch, or CambridgeSoft Chemdraw, if you need it for biochemistry then CHembiodraw will be better, some more is ISIS draw, Marwin Sketch etc, in initial you need some practice after that all are easy for work.
however all have their on benefit which you can identify by the regular use!!
I have used Symyx(Accelrys) Draw, a "no-fee" software on Windows system for academic and non-commercial use. It is probably the latest version of ISIS Draw.
See http://accelrys.com/products/informatics/cheminformatics/draw/index.html .
On Mac OS X, I use ChemBioDraw in my work place, and ChemDoodle in my home and tab, but both are not free. See also http://www.chemdoodle.com/ .