By 8pm EST tonight beta 2 should be available and it's using our new (and largely untested in a large scale) distributed network environment we've been working on for the past several months which should, in theory, provide secure downloads at very very high speeds.
You download via Stardock Central.
However, if it doesn't work for you, report here. Some things to make sure of:
1) Make sure you pre-ordered the game already or have an active TotalGaming.net subscription.
2) Make sure you are using the California server (you shouldn't have to worry about this but..). From SDC that's tools->settings->Internet
3) Make sure you have your serial # in there. That's tools->settings->Galactic Civilizations II (or TotalGaming.net if you have an active subscription to hat).
4) Make sure you have "Show pre-release versions" checked off at the bottom of SDC.
5) Make sure the email you used to buy the game is the same one you are using for your Stardock.net account. This is important since it doesn't just know who you are. It has to match the email addresses when it activates it.
If all that fails, respond here. We will be working on this. Also, please report if it worked fine for you so that we can at least know others are able to use it fine.