I think I remember using those paints a long time ago. I was really surprised by how good they were for the price, but if you ever get serious about watercolor I'd suggest upgrading. Only use black and white for tiny details. To darken colors, add a little of their compliment (color across from them on the color wheel). To lighten, add water to dilute the pigment. Using black and white paint to adjust your values will leave you with dull, flat colors.
Brushes look like a really great find. I'd suggest picking up a larger round in addition to that set. Michaels/AC Moore/Hobby Lobby should have a very reasonably priced option. I use an 8-10 round for at least 60% of my painting, but maybe thats just my style.
I'm a big fan of big messy palettes, and my concern with the one you linked is that it won't give you enough room to mix paints. If the ones I previously listed are a little more than you're willing to invest, I'd suggest something like this:
I can't stand strathmore watercolor paper. It doesn't stand up to repeated washes, the texture is gross- I could go on and on. The one thing I believe you shouldn't skimp on is paper. It is so difficult to make a great painting on sup-par paper. I've found a few links to some of the best prices I've seen for Arches paper. Link 1
As far as miscellaneous supplies, its all about what you like and works for your budget. I picked up a spray bottle (like you'd use for cleaning) for ~$1 at target and it works just fine. Different techniques call for you paper to be various degrees of wet. Wet paint on dry paper will give you a completely different effect than wet paint on wet paper. Robin Berry's 200 Tips and Techniques gives a very thorough description, demonstration, and even pictures of all of those techniques. Or check out youtube- lian zhen posts videos of his painting process (but might not give the best tutorial- hunt around).
Sorry I'm such a stickler for pricey materials, but if you're serious about learning watercolor I promise its worth it. Send me a PM if there's anything else I can help you with- or if you need some help when your materials arrive.