What is the best hand-held device for my database of books?

[Jan from Ohio]

I have a database (excel - Student-Teacher version) of all my books (over 400). I would like to put that database on a hand-held type of device. So that when I go to a library book sale and I see a book, I can look it up on that device to see if I already have that particular book.

The device needs to be low cost to purchase.

Thanks in advance for any help you can give me.
Plus easy to use. I'm still a newbie to the world of computer-type of stuff.