Hi Edgar,
The discussion you have started is very interesting. Salary for any employees Saudi's or Expat's is based on the companies internal salary brackets and capacity to pay and mostly are based around Saudi Labor Law to be on safer side. Please do note that contracting companies differ by and large from the direct staff's of companies and here lies the difference in the breakup of salary, which in most case are better with direct staff.
On an average accordingly to my analysis :
Unskilled Categories (5th pass to High School with few technical/computer course) - Basic SR1500-4500
Skilled Categories (Exp 3yrs and above with min higher Diploma or Graduation) - Basic SR6000-25000
Also I would suggest you review
<link outdated-removed> ( Search On Cite | Search On Google ) an
www.gulftalent.com salary surveys, which is worth considering.
Ukmitra