Do you write a "thank you" card after your 2nd interview?

Absolutely! A hand written thank you note is definately in order. Recap some of the things mentioned in the interview. Thank them for the time.

I've never heard of giving thank you cards after an interview. I'd say no to that.

Better too much than too little. I would tell the new folks that you enjoyed meeting them and thank the original interviewer for introducing you to them.

Yes. Send them all a hand-written thank you card.

Once should be enough. Its great to seem eager, but you don't want to be overwhelming at the same time. The kind sentiment you sent originally should be sufficient.

I dont think so. It kind of make you look a little desperate. But you sound like a nice person for asking.

Yes....but when you type the "Thank you" letters you are supposed to "cc" the other people at the bottom of the letters.

No I do not believe that you need to, obviously the first one did the trick. Good Luck!!

By all means, send them thank you notes or e-mails! Good luck!

Definitely, especially if you really want to work at that particular company.