I'm developing an address book for Gnome. You can find last version
on
http://digilander.iol.it/nfragale/download.html
(english pages are http://digilander.iol.it/nfragale/download_gb.html)
It support personal data (name, address, ...) emails, web urls, telephone numbers, notes, jobs notes (company where contact works assigment and more)
Data are stored in xml.
Nicola