What they said (CPL needed to make money, CPL requested to volunteer almost everywhere, visas...), but forget too about firefighting!
For some reason, itīs often seen as an easy way to get hours, an easy job to get... Let me tell you it isnīt. Those 'little' planes tend to have turbines attached to their noses and moving those propellers, so youīre not gonna get into one anytime soon after you finish your CPL. Then of course, the operation out of miserable lines barely visible on the ground where you wouldnīt drive your 4WD that sometimes we call landing strips, the coordination of the attack with the other planes and the guys on the ground, flying a very heavy plane down low, releasing 60% of your weight in a couple seconds right there, trying to keep the thing from stalling (and a stall with high power, on a high power to weight ratio plane, near the ground, isnīt a thing youīre gonna enjoy)... Nop, forget about that unless you have it as a final goal, because thatīs what it is, not a step to get to the airlines.
Volunteering in Papua, Africa... theyīre gonna have tons of commercial pilot CV's available, yet, the tendency is to call only those with a truck load of experience, as in "we donīt want time builders here"; and not without a reason, since the areas of operation tend to be rather difficult.
Now for something a bit more positive, you could try with the gliding or skydiving
clubs. They often have their good share of commercial pilots available 'at home', but maybe youīre lucky and hit the right one. Then, the older guys owning a private plane in your area; those that trained with you for their PPLīs or those at the airport that saw you start flying... Itīs not all that rare that they 'adopt' a youngster they know as their co-pilot, letting him fly and log the time. Not that you can make 100 hours per month that way, but itīs fun and theyīll be the happiest guys in town if you pay a meal every now and then
Cheers