Firstly, I'm going to recommend Astrobyte:
www.mainbyte.com/astrobyte/
Astrobyte is a computerised logbook. It gives you photographs and information about every messier object, a map to find each one, and a form to fill out when you log it. There is also logging facilities for each NGC object and many others. I use it on my laptop during a session, then fill out my proper "real" logbook afterwards.
Now, here is a big list of astronomy software, freeware, shareware and commercial. More than likely you have seen it before. But if not, this is a good site for various bits of software you might not have ever thought of before.
www.midnightkite.com/software.html
Hope you find that site useful.
  