This is a list of art supplies that I use and that I would highly recommend. I've selected them for their quality and also affordability.  Click on the links to purchase them. 
Watercolours // Half Pan // Suitable when travelling

In my experience Winsor & Newton's watercolours are the best on the market. The pigments are vibrant and the consistency is creamy, which allows you to use the paint in different modalities; Whether you are using watercolour in a more conventional way or not, they will bend to your needs. I only use pan watercolours as oppose to tubes. I love pans! You will only use up what you need and you can take them with you when travelling. I am always pleased with the results that these pigments give me. When you finish up a colour you can buy a replacement and fit it back in the empty slot. Removable pallets in this set allow you to clean them thoroughly; I'd recommend soaking the palettes and then using a soft sponge as oppose to a scourer as to avoid scratching the surfaces.

Click to purchase:
Winsor & Newton, Half Pan

Watercolours // Mini Pan // Ideal for day trips

I adore this set. It's small, portable, super cute. Same watercolours as above but you only have the essentials. Again, you can swap pigments pots if needed. This was my very first set I bought and I fell in love with it forever. It comes with me everywhere. Super reasonable and yet the quality is outstanding!

Click to purchase:
Winsor & Newton, 14 Pieces

These are some of the books I go back to from time to time when I need a little inspiration... 
It's a list in progress! 

The Artist Way // Julia Cameron

One of the most powerful and inspiring to me was The Artist Way by Julia Cameron. This book is great for anyone how wishes to do art but feels blocked in some way. Julia has a very unique approach: very honest and holistic, and I feel really aligned with her work. I had the pleasure of meeting Julia Cameron and get my copy signed by her, I still treasure it and go back to read it when I feel that I need a little bit of 'Coaching'.

Breaking into Freelance Illustration // Holly DeWolf

Excellent tips and advice from Holly DeWolf. Features several artists and gives you practical examples that will help you in your freelance practice.

The Illustrated Guide of Law and Business Practice // Association of Illustrators

Not exactly and exciting read by any means, but it will give you all the technical information you need to become a profession illustrator.

The things you only see when you slow down // Haemin Sunim

Jonathan Livingstone Seagull, a story // Richard Bach

Alice Adventures in Wonderland and Through the Looking Glass // Lewis Carrol

Poems // Emiy Dickinson

Leaves of Grass // Walt Whitman