Here is a list of software I am using for my CNC projects:

• CAD: ViaCAD 2D/3D
• CAM: CamBam and BobCAD-CAM
• Milling simulation: Cutviewer
• Speed/feedrate calculation: G-Wizard calculator
• Gear CADCAM: Gearotic Motion
• G-Code editor: NC Corrector
• Machine control: LinuxCNC

Some good sources for tools and materials:

• Cutters:
  • http://www.cncfraises.fr/
• Materials:
  • http://www.blockenstock.com/
  • http://www.qualichutes.com/

Here some other useful links:

• Another speed/feedrate calculator: http://zero-divide.net/
• CNC-6040 manufacturer: http://www.cnc-shop.ch/
• Very good forum with many informations: http://www.usinages.com/forum.html
• CNC machine kits and good forum: http://id-conception.fr/
• 4 axis CAM: http://www.cncwrapper.com/
• Fast prototyping CAD (up to 5 axis): http://www.deskproto.com/