The best thing you can do is to go to some old threads here on Dn Forum......there are some good ones that go back to 2003 or so, I think. If you put in a few hundred hours and start at that point, you will be able to work your way up until this point today, in 2010. When you are done you will have a unique understanding of where the domain industry is, and you will see some names that are worth six figures today that were sold here for a thousand or two, right on the forum. You might even see a few names that could be worth seven figures.
You will also see some interesting trends, like the history of 3 letter dotcoms. That is about the only thing that you could truly call an asset class when it comes to domain names. At most all times there is a certain minumum amount that 3 letter dotom's command. I think it might be 3-4K right now, though a few years ago it was closer to 7K or so, and before that they were sold for just hundreds. People tried to create asset classes out of 4 letter names, hypen 3 letter names, etc., but the 3 letter dotcom is unique in that you are guaranteed to always be able to sell immediately for at least the current low range of the worst letters. I had a good one a few years ago, and even though I do not have any now, it is still interesting to follow the trend.
You could also go to Dn Journal and check the top 100 yearly sales. I think they go back to 2003 or so. It is very interesting. I would stick to paying attention to the dotcom sales, as I know for a fact that there are many scammers in the other extentions who have had their bullshit sales published at Dn Journal. It is still a respectable place to follow the industry, though.
You might want to check out ElliotsBlog.com, RicksBlog.com, as well as SevenMile.com. For SevenMile.com, you will need to go back a few years to read some posts. If you see some members who post now who have had accounts here at Dn Forum since 2003 or 2004, then it might be a good idea to go back and read all of their posts for the last 6 or 7 years. If they are still in the game then they have done some things right, so it would be smart to follow their journey.
All of the information is right in front of you, you just have to show a little savvy and use your head.