I'd like to install Windows 7, Fedora and Ubuntu on my macbook.

Now I have mac osx and 3 empty fat32 partitions. I already tried installing Fedora, while Windows and Ubuntu where installed, but then something went wrong and I couldn't boot one of these 3, only mac osx was booting. The error message was: "no bootable device insert boot disk and press any key".

So, how do I install them correctly? It seems that the problem was with Fedora. In which order, and where do I install the bootloaders? On the partition itself or somewhere else?

Please help