The Igo series gives you a great place to start for dripping atomizers. Cost is low and quality is good. If you want to build single coil, go with an Igo-L. For dual coils, go with an Igo-W. Of you don't mind clones, you can buy copies of more expensive attys. The difference usually being just the quality of materials (grade of steel) used. In the clone world, Magma's, Plume Veils, and TOBH's are a popular choice now. They give you the option of adjustable airflow and single or dual coil set ups.
When building mech, read up on battery safety and definitely have an ohm reader. I would start wrapping coils with 28 gauge wire to start. Stay away from 26 gauge or lower until you're very familiar with how your wraps are coming out and how your mod reacts to lower resistances. I find that a 0.8 - 1.2 ohm build is a nice way to experience a mech mod/RDA vape. If you go lower than 0.8 to start, you may get a vape that is too hot or too harsh, therefore tainting the experience for you. As you drip more, you'll get use to the intense flavor of an RDA and may decide to test other builds. Once again, battery safety is number one.
Good luck! Hope you find dripping as fun as I do
