I work from photographs mainly.
For graphite/pencil illustrations I use a wide variety of tools. Leads from H8 to B8 - blending cones, I like to use microfiber cloth for blending - erasers - my secret weapon (for ultra-fine work) are mechanical drafting pencils at 0.03 to 0.09mm.
Pen techniques include brush and ink - ultra-fine draftsman rapidigraph technical pens - ultra-fine sharpie pens.
I prefer vellum bristol board at 11x17" or 12x9"
For computer illustrations I use Adobe Photoshop, Illustrator, and a Wacom Intuos digital tablet.