Meanwhile I'm waiting for Design for Hackers do you know any good design resources, as many I love designs by 37signals and I'd like to start making my websites look like that.
(I'm assuming you mean something like user interface design, not e.g. OOP design.)
A must read is Donald Norman's Design of Everyday Things
If you want a very good overview of how the human visual system works and how this can be used for design, I'd recommend Colin Ware's Visual Thinking for Design
Both books are very general. They apply to any kind of user interface (mobil, web, client...). I'd also say that both are timeless. They're not about the current vogue in UI design, but about the general percetual and logical properties any good UI must have.
Do not confuse usability design with aesthetic design.
While they can meld at points they differ greatly. Your aesthetics can generate visual euphoria while your usability makes using the product (web site, web application, desktop application, coffee machine, automobile, etc..) a difficult and cumbersome task.
Make sure you understand the differences as they are key to a successful .
A book applicable to usability design is Don't Make Me Think which I highly recommend.