Arrakis mentioned an announcement coming this week sometime. At which point we will likely know just a little more, even if only that it will be another week or two.
At the point when they are ready, all alpha testers with the gold names will be given download instructions via their locked forum. Once ready for more of us, the team will be adding download instructions for us as they decide is best (not sure if will be a full public post, or if they will add in a number of people first via basis on forum and bug report activity which has been mentioned as worth some consideration.)
Once we have access to the beta, we can play the beta and help test the MMO functions as they come. The actual currency and game copy which you have mentioned should be given to us as release items, although the client may well stay the same from beta to release, as that happens a lot. Likely the beta will not require us to expend the currency unless the team feels they need more testing of that function working (just my guess) and so you will not need it during beta.
That's just generally how things work, and what I have seen here. The team will, of course, have the final say on things. Sit tight, be patient, and we will be in beta before long!