Ok, here are the deductions that I am aware of you would pay on that salary:
11.75% (120,000) to 13.64% (140,000) - it is listed on the Zurich tax service at: http://www.steueramt.zh.ch/html/steu...if_a_QSt06.pdf
Insurance - accident (0.75%)
other - like travel cover and stuff is possible also, but not definitely maybe for 1%
Social security - AHV (state pension and disability) - 5.05%
ALV - Unemployment - 1%
Pension - probably around 5% (hopefully matched by the company)
Other cumpulsory contributions? Like union fees? nothing I think. You might want to open a retirement account ("Pillar 3a account") which you can put a bit over 6000 per year into and not have to pay tax on that money (well you get the tax back at least)
Medical insurance - you need to pay this yourself. from 175-300Fr per month
Council or poll taxes - all included in Quellensteuer
For the permit - demand a B, don't come for an L, you wont get a C. You have problems renting a movie on a L, its brutal...
30% is a good rough number (including medical) you can use for calculating, it shouldn't be any higher...