If, I may expand for a moment, I think that busking may be the best venues available to acoustic, contemporary singers. The traditional venues (clubs, festivals, coffehouses) are few and, except for very established draws, they pay poorly. (Unlike rock, acoustic is not often presented in bars with bigger entertainment budgets). The big problem with busking is that it helps if people see you every day, get used to you and look forward to seeing you. That means that it is tougher to hit a town for a couple of days and clean up on the streets.
Good luck on your adventure.

                Mike