I'm a web designer and I find myself a bit stuck because of lack of creativity. Do you have any advice, maybe some books or whatever to find some creativity again?
One thing i have found hugely helpful is looking for and keeping images of precedents, new ones for every job. They don't need to be from the same industry or field; in fact if they aren't, all the better because it will help you avoid the trap of simply copying and will force you to pull out the concept in a critical thought process. For example, i often enjoy looking at advertising for inspiration for landscape/architectual designs, even if its just the colour palette, simple form, or the arrangement of devices.
As for sources, they are everywhere:
And then draw. Sketch all the time - even if your not very good. Designers are primarily visual thinkers and we need to let that flow out. I even find myself just scribbling without purpose just to get started. Sometimes its just starting something is the toughest block to get past.
Remember: 'Creativity' never just a brain-flash moment of brilliance, and sometimes you won't even get one of those at all. A design always needs to be worked out bit by bit; refining, critiquing, adding and subtracting, to get the fullest solution