One of the apps that I tend to use a lot to find locations is Campendium. It’s free and you can filter by price if you’re looking to boondock. It’s also helpful for finding dump stations, and the reviews by other campers can give you insights into how safe or reliable the camping areas are. You can also link to campsite web pages from the app. I also tried RVLife app, but didn’t like that one as much.
As far as potential work, if you’re physically capable look up temp services in the towns you plan to go through. They are usually pretty easy to get set up with, and sometimes you can find a few days work to get you through. My husband does this in between construction jobs. You can google what towns have these type of offices. A couple of the more well known ones are PeopleReady, Labor Systems, and Allied Forces. So if you are planning on staying somewhere for a little while to get money to move on, something like that could be an option to help you out.
Also, if you are starting in January, Sedona might not be an option. Always check the weather in the area you are driving through. Even Sedona can get snow in the winter, and the campgrounds may not be year round. Also, while going through AZ, coconino natl forest is very picky about people staying on the land. They make up their own interpretation to the federal rules for disbursed camping, so if you’re staying longer then a night or two don’t be surprised if you are approached by a forest ranger and questioned about the length and reason for your stay. Keep your site clean, and “we’re here for recreation” is always the answer.