tourist visas don't include legal work permits, but there is of course off the books work.. Aka 'under the table'.
Though those situations result in doing the task, then having been not legit , not paid, and have no recourse to redress.
its,
http://www.ctc.org.uk/ US has ACA
http://www.adventurecycling.org/
http://www.hihostels.com/ US hostels not as common , major cities , yes..
buy IYHA membership card at home or 1st overnight
and other people's trips, here:
http://www.crazyguyonabike.com/?o=lt