Have a look at Trend or Rutlands Just about any router bit you can think of. If you are looking at true CNC router cutters, have a look at Routercutters UK but I hope you have deeeep pockets. :-)

As for Aluminium, standard milling cutters do the job nicely as you'd expect. It all depends on your spindle, if it a colleted type you can pretty much use any that will fit, if you are using a router then your choice is more limited as they need to have standard shank sizes or an adaptor to bring them up to your collet size.