If the shoes are all-synthetic (like most Evolv shoes), you can wash them with soap and water. If not, then what jumpuphigh said, disinfectant spray.

ETA: Completely forgot to say yay for getting back into it! Also yay for cute guys who want to talk climbing. *g*

ETA2: Speaking as one anxious person to another: climbing chalk is magnesium carbonate and does not decay. The only bad thing I can think of that could happen to it would be if it had been stored somewhere damp, in which case you would have damp chalk, which would presumably be less useful.