1. A thank you gift basket is a common sense way to show appreciation. It illustrates thanks without being effusive and provides immediate reciprocity.
2. If you don't know what kind of food or goods the person to whom you'll be sending this thank you package prefers, we recommend chocolate. After that, some nice wine. But really, you can't go wrong here.
3. Appreciation is a funny thing. Nobody does a favor expecting something in return, yet nobody accepts one without to reciprocate. The thank you gift basket is an easy solution.