http://www.fpi-protostar.com/
Supplier of high quality Dobsonian/Newtonian secondary mirrors, spiders, mounts, tubes, flocking material etc.

http://www.starlightinstruments.com/
Manufacturer and supplier of high quality Feathertouch focusers for many models and brands of telescopes.

http://www.focuser.com/
Manufacturer and supplier of the popular Moonlite focuser.

http://aavso.org/
Astronomical Association of Variable Star Observers.

http://svaatest.site88.net/
Snake Valley Astronomical Association is a small but enthusiastic club based in country Victoria (Australia).

http://www.astrosurf.com/rondi/jupiter/
Jupiter 2.0 is a software for the calculation of Jupiter's satellites ephemeris, with a graphical view of the jovian system.

http://ssd.jpl.nasa.gov/horizons.cgi
Very handy ephemeris site for all planetary objects.

http://www.astronomie.be/registax/
Registax is the very popular freeware imaging software package which allows you to manipulate and stack multiple images.

http://deepskystacker.free.fr/english/index.html
DeepSkyStacker is a freeware program for astrophotographers that simplifies all the pre-processing steps of deep sky pictures.

http://www.charlieduke.net/
Charlie Duke, Apollo 16 Lunar Module Pilot and famous Apollo 11 CapCom voice.

http://www.nasa.gov
Official site for the National Aeronautics and Space Administration.

http://www.nasa.gov/multimedia/nasatv/index.html
NASA TV internet channel

http://www.hq.nasa.gov/alsj/frame.html
Apollo Lunar Surface Journal. Contains lots of documentation on the Apollo program.

http://hubblesite.org/
The official site dedicated to the Hubble Space Telescope.

http://www.thespacestore.com/
All manner of space related items including mission patches, models, replica space suits, books, posters and more.