Another good place if you want the definitive specs you'll need to comply with is here .
Just in case you hadn't noticed, designing a mobile phone (cellphone) circuit board is going to be a little more difficult that designing one for a 555 timer.
I work for a phone manufacturer and we have whole teams doing circuit board design using some expensive software packages.
Have you identified which processor, DSP, wireless modem etc you are going to use ?
by Jake Hertz
by Duane Benson
by Duane Benson