Tool Panel in Photoshop CS5
The Tool Panel is located on the left of the Photoshop environment.
To access the different tools either click the small triangle in the bottom left of each tool. Alternatively press Shift then the key board short cut for each tool. If you hold down Shift and press the keyboard short cut several times you will cycle through the tools e.g. Shift and L x3 will select the Magnetic Lasso Tool.