Hello, my name is ***** ***** I will do my best to assist you. Give me a few minutes to look over your question and I will respond shortly.
There used to be a very helpful Add-On called Email Address Crawler but it no longer works for the latest versions of Thunderbird and the author is no longer updating it. You can add contact by using this forum post.
Then you can export the address books to a file that can be moved via USB drive and then imported into Thunderbird on the tablet. This link below has a step by step process for exporting and importing.
Let me know if this worked for you. I'd like to make sure you're satisfied.