It all depends on what camera you have.
Gphoto is the program thats most widely used and supports the highest number of cameras.
www.gphoto.com
If you have a kodak DX series like me then you should check out mmptp. Its a command line utility for getting the picture off your camera.
http://www.michaelminn.com/linux/mmptp/README.html
Once you have the pictures off your camera you can touch them up and edit them in the G.I.M.P.
www.gimp.org
gphoto and G.I.M.P. should come with most distros.