Information about Zappa you can find on newsgroups like alt.fan.frank-zappa and alt.music.frank-zappa.
These sites are still up to date
What can I say?
The Home Of Frank Zappa Heritage Studies by Vladimir Sovetov Russia
a Zappa site with lots of info by Jurgen Verfail Belgium
Songs, chronology, etc. by Román García Albertos
Argentine vinyl by Marcelo Gasió Argentina
Zappa singles by Kristian Kier Germany
Every Zappa GIG by Charles Ulrich
a nice big Dutch link site by Fons Sleijpen
a search OF FRANK'S CATALOGUE by Chris Sansom Highway 57
a site Dedicated To and For His Music's Collectors..... by Romano Manara Italy
FRANK ZAPPA - Bootlegs and more ... Didi , Phil & Forest Real Crazy Zappa Devotees Recording Work Team