Address Book question

Hello, thanks for this great site and great apps. I've bought myself a 1GB USB 2.0 flash disk (had a 1.1 USB 1GB before) after I discovered the site and copied the portable apps into it. For now, I use the Portable Thunderbird and it rocks, to be mobile and not to worry whether my important email message is at home or at work.

I used TheBat Professional Edition before. It is a VERY advanced email client but despite that it had very little community support and as of yesterday, I jumped on the Thunderbird train.

I've imported my previous mailboxes with absolutely no problems. All I had to do was to export Unix mailboxes from TheBat and copy them into my account directories of PTB.

My question is about the address book. I managed to export a ldif file from TheBat (name: addressbook.ldif), then imported via PTB. It created a seperate addressbook with the name addressbook. However, I'd like to have my emails in my Personal Address Book. No matter what I do, I can't move them into Personal Address Book. I have 3 lists in my "addressbook".

Personal Address Book
-addressbook
-list1
-list2
-list3
Collected Addresses

that is how it looks. Any advice?

Where does PTB keep the addressbook file(s)?