Links will open in a new window or tab: 

  General Astronomy Links (many are organized by multiple topics)--

AstronomyLinks.com <astronomylinks.com>
Astronomy.net <www.astronomy.net>
Astronomy Web Guide <astronomywebguide.com>
Astronomical Leage <www.astroleague.org>
Astronomical Web Resources <www.stsci.edu> Massive list of professional sites
Ash's Astro Links (look in Resourses on right side of page for links) <astro.ai-software.com>
IMS (huge list) <www.intricate-ms.com>

  Lists of Astronomy Clubs & Societies--

ASP: Astro Clubs <www.astrosociety.org>
AL Member Societies <www.astroleague.org>

  Space & NASA Links--

Aerospace (NASA) <www.ksc.nasa.gov>
Space and Astronomy <www.refdesk.com>

  Lists of Astronomy Software--

Arnett's Software List <astro.nineplanets.org>
Intricate's List <www.intricate-ms.com>
AstroTips (astronomy software downloads, reviews, & discussion) <www.astrotips.com>

  Astronomical Calculators On-Line Using Java

 Java for Astronomy <http://users.zoominternet.net/~matto/Java/>

  List of Amateur Observatories--

Arnett's Observatory List <obs.nineplanets.org> huge list!

  Lists of Commercial Astronomy Products & Vendors; Product Reviews--

Products & Vendors: <astronomy-mall.com> 
                                   <www.sjaa.net> 
                                   <www.astronomy.net/astroguide> 
                                   <www.astronomy.net/astroguide/manufacturer>
Product Reviews:      <www.best-scopes-n-binoculars.com> 
                                   <www.cloudynights.com>
                                   <www.scopereviews.com>
Vendor Ratings:        <www.excelsis.com>

  Yahoo Groups: Telescopes: extensive lists of astronomy related vendors--
   Note: you will have to join the Yahoo group "Telescopes" in order to access these links.

Telescope Vendor Links:
  <groups.yahoo.com/group/telescopes/links/Vendors_Dealers_000966490250/>

Telescope Mount Vendor Links:
  <groups.yahoo.com/group/telescopes/links/Telescope___Mount_Ma_000966492797/>

Accessories Vendor Links:
  <groups.yahoo.com/group/telescopes/links/Accessories___Other__000966576982/>

Astrophotography/CCD Vendor Links:
  <groups.yahoo.com/group/telescopes/links/Astrophotography_000966578467/>

General Page of Astro-Related Links: <groups.yahoo.com/group/telescopes/links/>