I agree that tools for finding articles in back issues are helpful. Paul Friberg and I constructed such a database, and it has been available for a few years at:
http://www.ldeo.columbia.edu/~paulf/paulf.climb.html
and
http://www.stanford.edu/~clint/magindex/magidb.htm
I'd be interested to see how your index compares with ours.
I believe Climbing magazine has a back-issue search on its web page
www.climbing.com . There is also a printed index to back issues of Climbing (I'm not sure how often it is updated).
Clint Cummins