Check the clearance stuff, then take a photo and buy the rest online. When I went to the Blick's store it was 1/3 more expensive than the same stuff at their online store. Ugh. I love their watercolor paper! We used it for homeschool, and it was fun to play with. I bought some of their 60lb/80lb drawing paper and we used that a bunch too. I liked to buy 12x18 and cut it in half because it's cheaper. I found their supplies to be high quality for the price. When you go to the store, feel the paper so you get an idea of the thickness of each weight. I bought paint palettes from Blicks online because they were a better price/quality than the dollar store or Target.
Another place that has some good paint storage solutions is the Lakeshore Learning Store in Henderson. Yep, geared towards teachers, but teachers with small classrooms who need to store stuff! It'll be kid patterned, but they have a fabulous table cover that's nice and thick and gives you confidence that it won't let paint ruin anything underneath. It's long lasting. I also bought their No-Spill Painting cups, but YMMV on whether you tip things a lot like me - or are neater. Somehow my clothing always catches my water cup and tips it over! Ugh.
I do use the Hobby Lobby Master's Touch Acrylic Paints for painting miniatures. I like it. I don't know how it would work for AJ, but I like the texture, and it's easy to thin when needed. I waited until it was on 40% off sale or I had a 50% off coupon - I don't recall which one. But it made it cheap to buy a bunch of colors and play with them.
I would say remember - it's fun! I bet you've done Art with Melissa over the years and had fun. Start there!