Welcome to the game!
first of all, it's not your fault for joining the guild and losing your subscriber status, it's a known bug (listed on the customer support forum) and EAware is hopefully working on resolving it.
This said, if you've enjoyed playing with the people you met in that guild, nothing prevents you from adding them to your friends list (hotkey "O", there is a "+" button at the bottom right of the window to add a friend). You'll be notified when people in your friends list connect and you'll be able to know where they are.
you can then whisper them (type "/w <your friends name> <your message>") or if they whisper you, you can reply (type "/r <your message>" it will automatically fill the name of the last person who whispered you)
As for finding another guild to join, the best place to do that would be to head over the forum section dedicated to each server. There is also a sub forum for each of these server forum dedicated to guild recruitment.
Thanks so much for your reply. Please forgive me for such a newbie question, but how do I learn what server I am playing on?
One thing I have found a little tricky with this game is the difficulty in finding answers to what are probably common questions. Efficient tutorials built into the game could help a lot of the newbs such as myself. This is not meant to be a negative comment, just an observation.
The complexity and detail in the game is superb. It's sure to keep my interest for a long time to come. Being and old retired phart, I have a lot of time to devote to the game.