Lookin for specific Pro Sites Data in the MySQL db

Hi Folks

After Digging through the tables, I havent been able to find the following info, any ideas as to where is stored.

Pro/Premium Date( the date they signed up as pro)
Next Billing or Expiry Date (This used to be in a unix tine stamp format under the column expiry, but cant find it now)
Subscription Plan or Level (users' selected plan)

The reason we need this is to pull the info into an external affiliates system with a mysql query, so we would also need to be able to search the tables for blogs which have upgraded to a pro site, the only way i can see this at the moment is to run a query and see if a subsite has an expiry date or not.

Any help would be much appreciated,