I have Compaq Presario C700 Widescreen laptop , my microphone which is next to web camera is not working,

You can use Windows Vista (please chose 32bit or 64bit file) driver, and later you can use manycam.com's webcam software.
http://h10025.www1.hp.com/ewfrf/wc/softwareCategory?cc=us&lc=en&dlc=en&product=3559331

Your cam's driver won't work properly or install your cam's driver correctly with compatibility with your motherboard.

CHECK THE SOUND DRIVERS IN DEVICE MANAGER

If it has Realtek device drivers check through that not WDM. Also, make sure you set the record settings for the mic to select it, not the play settings.

At first let me tell you should have Operating System Vista for the inbuilt mic to work to get the full performance as it has the drivers. Got to Start>All Programs>Accessories>Entertainmnet>Sound Recorder. You can check the mic is working or not.
Regards

i have compaq Presario c700 laptop
but my external microphone is not working & also inbuilt microphone is not working.

Im looking for a webcam driver for my Compaq Presario C700 my laptop camera is not working

I HAVE NO AUDIO DRIVER COMPAQ C700

i have compaq presario c700 laptop how do i find my sound driver ?

Just download audio driver from this link

http://www.mmoogle.org/compaqc751nrwindowsxpdrivershowto

I am sure it will work.