Discovery by Sketch
Starter Art Supplies for Quick Sketching
I use most of these products all the time -- as well as many others. But these will give you ideas.
All the links below will take you to the specific products on Amazon. Yes, I will receive a small affiliate commission, which won't change your price. Feel free to use the recommendations to purchase at another store. However, if you live in rural Alaska, Amazon is one of the most affordable options. I also highly recommend arttoolkit.com.
Sketchbooks & Paper
Any sketch paper labeled SMOOTH or FINE TEXTURE will work
I prefer stitched bindings because then you can draw right across the binding, which doubles the size of your page. However, wirebound books have a wire binding which means you can easily remove pages.
Pens & Pencils
Avoid pencil sets with multiple hardnesses -- way overkill
Adding Wet Color
ArtToolkit.com: Excellent watercolor palettes, paint, and brushes with affordable, efficient shipping: