help needed!!!

hello everyone,
i am doin two projects........first is "hitec security system" ........and second is "trigerring electronic devices by gsm tech"
in my frist project i use a LDR at the entrance pointed to it is a laser source...when somebody obstructs the laser light interrupt is ent to the pc thru parallel port and the pc sends a message to the gsm modem and the gsm modem sends in the message that some one is at the door.

in my second project a messsage is sent to gsm modem thru a mobile .....this gsm modem interrupts the pc and then pc triggers the elctronic devices connected to the parallel port.
My question is where can i get the necessary information regardin the above two projects??????i will ask my practical bottlenecks in my next post

ur description is straight forward . now..
u'll have to know how to access the parallel port from OS (win2k+??).
then have a look for SMS AT commands , i think documentaion availabe for nokia sets.
biuld the system part by part ,, debugging each section.

where?\

where can i find the documentation???thats wat my question is?cud u please tell me this?

have u tried google..??
for SMS
**broken link removed**
**broken link removed**
for port access
**broken link removed**
HTH