Here are a few Astrobiology links to get you started. Links specific to weekly topics can be found on the Schedule page.
Astrobiology glossary - at the NASA Astrobiology Institute
NASA Jet Propulsion Laboratory
Astrobiology at Other Universities:
NASA Specialized Center of Research and Training (NSCORT / Exobiology)
University of Colorado Center for Astrobiology
Penn State Astrobiology Research Center
Other Astrobiology or Astronomy Links:
Astrobiology Web - Encyclopedic in scope, but some links don't work.
XLife - an outreach project aimed at middle school children. Has good information, though.
David Darling's Astrobiology Homepage - has good links, but beware the pop-up ads and phallic symbols.
Planetary Rising and Setting - gives local times for the rising and setting of the planets.