Can not boot after update to 10.4.11 - 'NTLDR is missing' comes up.

I have recently updated MAC OS X 10.4.10 to 10.4.11, installation has been completed and I've been prompt to restart my MB Pro. Restarting the computer ends up in text screen saying:

NTLDR is missing
Press any key to restart

To explain ... I use to had a BootCamp installed on my MBP and it has split HDD into two logical discs. I have uninstalled BootCamp ages ago and never had any problem with it up until now (I ended up with the HDD split in two disc but it kind of suited my needs, so I didn't bother joining them).

To have it even more difficult, I don't have any installation or recovery discs with system. My wife bought the computer about 3 years ago from authorised dealer in Spain (that's where we live) and ask them to put the OS into English for her. That involved waiting a couple of hours for the shop to do it. They've done that, but they kept the discs. We never really needed the discs so we did not bother to take an 1 hour drive to the city to hassle the shop.

reboot while holding the option key - it should allow you to select your OS X partition

Then go into System Preferences / Startup - select your MacIntosh HD as the startup disk and click on restart now

Let us know the result

It does let me to choose a disk I want to boot from, but both of them result in the message:

"NTDLR is missing..."

I am going to see the Apple dealer and try to get the discs from them. Will post the results of the meeting.