I need to replace my Sony vaio VGN-N series laptop hard disk. Can you send me the instructions please, as i have know idea. Thanks in advance.

The VAIO VGN-T350 is a notebook computer designed and distributed by Sony.
The hard drive on your Sony VAIO VGN-T350, which is the unit that stores data, consists of many clusters of data that can be rewritten with new data.
If you are looking for a memory capacity upgrade, or if your old hard drive is having errors, it's time for an upgrade.
Upgrading the hard drive on your Sony VAIO will require the use of a screwdriver and will take you about 30 minutes to complete.

Turn off your Sony VAIO VGN-T350 and remove the power cord and any other peripheral components.
Turn over your Sony VAIO VGN-T350 and locate the hard drive chamber on the bottom of your laptop. It will be clearly labeled.

Use the screwdriver to remove the screw holding the lid in place.
Gently lift the hard drive and its cage away from your laptop and disconnect the data cord.
Remove the four screws located at the corners, and then remove your old hard drive from its cage.
Place your new internal laptop hard drive into the cage and replace the screws.
Connect the data cord to your new hard drive and place your new hard drive into its chamber.
Close the lid and replace the screw to complete the operation.
http://www.fonerbooks.com/laptop_1.htm
http://www.youtube.com/watch?v=rg_GvaMunas
Sony Vaio Hard Drive Replacement
This might not be your specific laptop it might give you an insight into the hard drive installation.

Ebay this hard drive should fit there are smaller capacity drives that will be compatible.
http://www.ebay.com.au/itm/New-500GB-Sata-Hard-Disk-Hdd-for-Sony-VAIO-PCG-3H2L-VGN-P530H-VGN-SR410J-B-/190882270487?pt=US_Internal_Hard_Disk_Drives&hash=item2c71784d17

500GB Sata Hard Disk Hdd for Sony VAIO PCG-3H2L VGN-P530H VGN-SR410J/B

Try this:http://www.sony-asia.com/support/download/60137/product/vgn-sz18gp

If you are still having the original hard disk holding alt + F10 at boot will start the factory restore process

You can buy hard disk for your model from following link at low price

http://www.laptoppartsexpert.com/c-47805-sony-vaio-vgn-vgn-s-series-vgn-s170p.html

See http://losercoalition.net/blog/2008/03/sony-s-series-laptop-disassembly-for.html

Hello

Well, the recovery disks won't allow you to go to your present system. The recovery disks are designed to put everything back the way it was when you bought the computer, minus all your applications and data. If it's your data that you need then a reputable repair service like mine can slave your hard drive to another system and recover all your data (not applications), provided the hard drive has not electronically or mechanically malfunctioned. Again, a reputable repair person can tell you the status of the hard drive.

Thanks

Please refer to the instructions at the following link:
http://www.insidemylaptop.com/how-take-apart-sony-vaio-vgn-sz-series-laptop/

If it is a hard disk password, you will need to take it to a Sony repair shop or send it to Sony. If it is just a boot password, clearing the NVRAM should fix it.

turn the laptop upside down ...remove a partial plastic cover attached by a screw on its edge ( there is a small sign showing the hard drive usually) after taking the cover of plastic away the hard disk is visible . pull it gently aside (sideway)
and replace it with the new one.

Possible hard disk failure or hard disk controller failure.
if you feel confident remove the hard disk and replace - obviosuly make sure that there is not power running and remove the battery - replace hard disk then battery then power and try again.

Do you get any beeps? is the hard disk clicking? listen carefully to it and post your findings.