Skill improvement handbook

[Lord Il Palazzo]

Is there a guide/thread/handbook somewhere to ways to improve various skills? Max ranks and a good ability modifier only go so far (and are only so plausible; not every character can afford to put enough points into wisdom to get +4 to spot, for example.)

I'm interested in spot, listen and sense motive especially, but something that addresses more than that would be an even more valuable resource.