Something I haven't done for a little while but I used to use a vector graphics package - in my case Serif's DrawPlus, unhappily no longer available - to generate my CD artwork, save the resulting label as a JPG which I then printed initially on a self-adhesive label using one from the Avery range or direct onto a printable CD. However any vector graphics package should be capable of generating these images, you could try the freeware Inkscape.
Printing onto CD's with a printable surface layer gave much more reliable results. Two problems with the adhesive label route - it is very difficult to get the label exactly centred on the disc which creates imbalance in the player and there is always a risk of the label partly coming unstuck and starting to shred in the player which does horrible things to the player ! But to use printable CDs you need a printer which can print onto a CD surface.
Chris Cosgrove