If you are looking for good introductory art lessons you may want to check out Art Graphica.  It is an online resource for instructional lessons, interactive demos and videos.  They do a have a section of free art lessons including pencil drawing, oil painting and watercolor lessons. 

The tutorials include step-by-step instructions as well as images.  Most of the lessons are for specific objectives, like 'drawing trees' or 'landscape painting' rather than general subjects.  You will certainly find some tips that will help you with your artwork - particularly if you are a beginner.

One of the best things you can do when you're starting out with watercolor paints is to create a color grid. Doing this will help you learn your colors. It will allow you to determine the gradation of each color, the transparency or opacity of each color, and the staining power for each pigment.

To make your color grid, you will make a space on the page for each color in your palette. Your marks on the page will be vertical and you will write in the color name for each color above the line you will make using that color. Before you begin making strokes on the page, take a waterproof black marker and draw a long, thick line of black horizontally across the halfway point on your page. Each vertical line you draw will bisect this line. Start simply with a thick black line across the page and vertical lines marking an area for each color you will add.