In almost every country where is rock is usually some climbing community. There are lot of local websites about climbing, but not every has a climbing forum, where you can speak with climbing community in this country. Here is list of climbing forums:
Argentina
?
Australia
www.chockstone.org/Forum/Forum.asp - Climbing in Victoria region
www.thecrag.com/climbing/australia/forum
www.climberswa.asn.au/forum/
Austria
www.bergsteigen.com/forum
Brazil
www.escaladabrasil.com/osite/modules.php?name=Forums
Canada
ontarioclimbing.com/forum/
www.climbeasterncanada.com/
squamishclimbing.com/squamish_climbing_bb/
www.gravsports-ice.com/icethreads/ - forum about ice climbing and also mountaineering
China
?
Croatia
www.planinarenje.net/forum/forum.php
www.hps.hr/forum/
Czech Republic
www.lezec.cz/diskuse.php
Finland
www.slouppi.net/phpBB3/ - bouldering
France
?
Germany
forum.klettern.de/forum/klettern-bergsteigen-und-klettern/
Greece
www.routes.gr/Community/viewforum.php?f=1
www.climbincrete.com/modules/forum/index.php
Iceland
?
India
?
International
www.mountainproject.com/forums/
www.rockclimbing.com/cgi-bin/forum/gforum.cgi
Ireland
forum.climbing.ie
Italy
www.forum.planetmountain.com/phpBB2/index.php
Japan
?
Mexico
?
New Zealand
Norway
Poland
Portugal
?
Romania
Russia
?
Slovakia
Slovenia
?
South Africa
South Corea
www.koreaontherocks.com/forums/
Spain
Sweden
?
Switzerland
Turkey
?
United Kingdon
www.ukclimbing.com/forums - Probably most popular climbing forum in UK
www.ukhillwalking.com/forums - Forum more about hiking, but I think that mountaineering can be also here
Ukraine
?
United States
www.mountainproject.com/forums
www.rockclimbing.com/cgi-bin/forum/gforum.cgi
www.supertopo.com/climbing/forum.php
I'm going to submit information about some websites about climbing. If you can recomend any, leave an info in comment or send me an email.