Hi Candi,
Actually, no questions are silly, we're all been there at some point or another. The coffee question, yes they bring it in a carafe, along with a cup, sugar, cream, etc.
As for postcards, yes, you can have them mailed from the ship, just buy the correct postage at the pursers desk, according to when you are mailing them.
I usually do this too, but don't expect the postcards to beat you home, they seem to take their own sweet time :-)
If you plan on sending/reading any e-mails, you can usually find an internet cafe on shore, most of them are right near the pier, much cheaper than onboard the ship.
Happy Cruising,
Donna
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