In reply to Rich2002:
May is a good month for climbing but already getting a bit hot. This site gives some info (you can ignore the "beauty" ratings, which are mostly not filled in):
https://www.falesia.it (Choose Trentino in the little map)
For muti-pitch semi-trad (recommended):
http://www.arrampicata-arco.com/
As for buying guidebooks ... depends how much time you dedicate to climbing compared to jumping (and whether you plan to come back, although you probably will if you are jumpers).
There are two very fat volumes (both also in Enblish), one for trad and one for bolt crags.
You could come and visit me one evening and "memorize" a few pages of my guides if you like. Good beer and food right next door to me, and cheaper than Arco. I'm in Cadine, the village just before Trento city. We could even do some climbing on my after-work evening crags. Come to think of it, there is a potential jump site near my house as well, but I doubt you are allowed to use it.