You can be just as creative with acrylics as you can with any other media. But like any media it has its strengths and weaknesses. There is a saying " The best thing about acrylics is that they dry fast. The worst thing about acrylics is that they dry fast."
The beauty of acrylics is that you have a great deal of versatility. You can apply them like watercolors, or very heavy impastos. Different brands have different viscosities. I personally like Utrecht, Golden, Liquidex High Viscosity and Lukas Impastos. I personally believe that it is easier to add water (or medium) than it is to take it away if it is too thin.
Since I don't know what effect you are going for, I don't have any specific advice for you. I have several years of painting with acrylics off and on, and eventhough I am still learning myself, I certainly will answer any question I can, or guide you to where you can find what you need. Just email or pm me if you have a specific question.
I will suggest a few books and a suggestion. First look for Acrylic Techniques by Barclay Sheaks. This is probably the best book ever written on acrylic painting. Most large libraries have it. Then look for any one of Rudy De Reyna's books on magic realist watermedia painting. They are 4 or 5 of them, currently all out of print, but I have found them readily available at libraries and used book outlets. Another out-of-print book is Color Exercises for the Painter by Lucia A. Salemme. While aimed at oils, and the author is an abstractionist, it has some of the best painting exercises for understanding color. I purchased mine online through Barnes and Noble for like $7 (They had one at the public library until someone lifted it). Also Blue and Yellow Don't Make Green by Michael Wilcox. One of the best books in painting color theory.
Finally, my best advice is to experiment. Take a variety of brushes and supports and just play. Don't build a masterpiece, just doodle. Find what consistency and support you like, and what tools grant you the look and feel you want. When you picked up your first crayon, you didn't draw the Mona Lisa. You scribbled and hopefully not on the wall. Just go and have fun. There are a variety of mediums and tools available. Personally, I like a good impasto medium, a masonry trowel, and a stiff bristle brush.
Have fun.
Andrew
