I searched around for something like what you describe several months ago and here's what I think:
Libra is a beautiful free application that allows you to import and export to and from text files (txt or csv), excel, or web (html). You can input or scan a book's ISBN number and the software will retrieve information about the book from Amazon.com and populate fields with that information. There are also some user defined options that allow you to add user-defined fields and you can also keep track of books that you have lent out or borrowed.
eLibPro is another free application that is written in Access, so there is an Access database that holds much of the information. eLibPro allows you to import from XML and export to HTML or XML. This was an issue for me because I had previously created an Excel file to keep track of my books and that file was quite large (I wanted to import all of that data into whatever software I used). However, since it is written in Access, it is easy enough to import data directly in the Access database and to export the Access database to a text file. Similar to Libra, You can input or scan a book's ISBN number and the software will retrieve information about the book from Amazon.com and populate fields with that information. You can also import a list of ISBN numbers into the software (this was extremely useful to me).
Collectorz.com sells a
BookCollector (standard & pro versions) application that I tried out, but thought it was overpriced and not so user friendly. If you already use ListPro (as the previous poster recommended), there is a ListPro template already set up specially to be used to import data from Collectorz. This is nothing special, you have to manually initiate an export from the BookCollector software. BookCollector has a programmed export template that cannot be changed so you are limited to only a few fields. I didn't find this much of a selling point.
With either Libra or eLibPro, it is easy enough to export the data to a CSV file and then either import it into Excel or into ListPro. These files could then be copied over to your pocket pc. Instead of going this route (I already own ListPro), I joined
GoodReads, and I am importing the CSV file into GoodReads, so my list of books is readily available online. I have hundreds of books to catalogue and I am nowhere near completion, but here's my
GoodReads profile, if you are so interested....
GoodReads has a
mobile website that is easily accessible from my Pocket PC. With a GPRS/Edge/3G connection, there's really no reason to have to install yet another Pocket PC application just so I can carry the file around with me on my mobile device.