Try contacting the Norwegian Trekking Association's (Turistforeningen) office in Tønsberg, I believe they have a climbing group. If not, I'm sure they can help you out with finding one.Contact them via http://www.tot.no/group.php?gr_id=50&fo_id=1059
There is a small wall in "messehall A" used by Norwegian Trekking Association's (Turistforeningen) in wintertime. It is no closed for the summer, sinse we have start climing outside.