restore osx bootloader

hello, this may be a simple question, but how to I reinstall the os x bootloader without the osx-CD?
The thing is: I tested Ubuntu just for a sec to see and try out, ya know? So I did this dozen of times before, and all worked, no problem. But now I get this stupid message, some like: "there is no bootable device, please press the "'any-key'"
I coudn't find the any key, so I just pressed any key, but nothing happened. After some rebooty things, I don't know what to do I can't get into my osx, ya know?
And big prblm is: I have no osx-CD, cause I left it at my other house, quite 9 hours away. what can I do???????
thx for helping

 

ok, problem solved. I don't know how, but it's working again.
to the moderators: please delete this thread.
greetings
tom