I've read most of the papers and journals on this topic. I'm looking
for the intuition and not the math.
1.) I need a definition of the concept of "wage posting" in the field
of search-theoretic models of the labor market. Why it is done and
how. I would greatly appreciate a quoteable reference.
2.) It would be great if someone could point me to a textbook as well. 
3.) Any hints about the history and development of this recent concept
would be nice.
  
TIA

Hi TIA,
Since you have asked for intuition and in your no. 3 for hints, I will
venture to offer an opinion about that one.
Here in Germany, where labor unions were once much stronger and there
are employee representative councils in many firms (if the employees
so decide), the tariff agreements between the unions and the
employers' or their associations have been very detailed: definition
of job content, age, training, etc.  The employee councils can oversee
the upholding of this system.
The system is not just something the unions have insisted on; any
major employer needs a system that assures a modicum of equal pay for
equal work.
Those last five words bring up the subject of equal pay for women in
USA, that is codified in federal and state laws.  Wage posting is one
way  - if not the only way -  to avoid disputes.  By defining
everything in black and white and posting the information, and then
sticking to the system, the employer has a better chance of avoiding
disputes and suits about discrimination of all types.

It is regimentation and may be a hindrance when hiring.  I guess that
the counter argument would be that the employer's system was
inadequately defined if
it doesn't have a wage slot appropriate and attractive for an applicant. 

Is that any help?  I hope so.
Regards, Myoarin