If you are serious an air brush and compressor are the preferred tools of the trade. You have much more control of the paint flow, and get a finer, smoother finish from the airbrush. But with careful work and good masking techniques, you can produce nice quality models with spray cans. Unless you are diving in full force from the start, the spray cans would not be a bad starting point. With spray cans you will have to mask off areas where you don't want overspray, because they throw out a lot bigger spray than an airbrush. I recommend Scotch Blue Painter's Tape. It does great at not pulling up previously applied paint. As far as paint, you will get a lot of opinions there. Humbrol is great paint if you have easy access to it. If it is a paint you are comfortable with then stay with it. I myself like ModelMaster enamels. Keep in mind cleanup. Enamels require solvent based thinners and cleaners, where acrylics need water based media.