hi all,
i'm trying to write a unix system from scratch (not re-writing the kernel)
does anyone have information about that? tips and stuff...?i would appreciate every help,
thnks 
Check this site out: http://www.linuxfromscratch.org. I believe that's what you are looking for?
thanks blowtorch, i wonder y it didn't show when i googled it!:S
Because you were searching it with keywords "UNIX from scratch" see here, its the first shot with key word "Linux from scratch" linux\ from\ scratch - Google Search 
Regards,
Tayyab
yeh you're right, thanks
did anyone tryed/did it?or has an experience in that domain?
That would be an interesting thing to know about if someone has really done any kind of research on this project and tell us about his/her expereinces with LFS.
I do have some (or rather more than some) experience with building an lfs system... First one didn't complete the build (probably made some stupid typo's... Second one went a lot better, LFS system worked and proved to be very stable... Added some stuff from the BLFS book and hey my own LFS/BLFS server was up and running... Has been up for about 4 months now, never rebooted, no problems till now 
Recently finished a LFS/BLFS workstation version with X-Windows & KDE, runs great on my Dell Inspiron (boot time < 20sec including XWindows)... only (small) problem seems to be the integrated Wireless adapter, but working on a solution for that ...
Server was build from a Fedora Core 2 host system on a P3-1800, Workstation on dual core dell 6400 with 2048mb ram... building took me about 3 weeks (only worked on it after my office hours though)
....
I remember when "from scratch" meant a soldering iron and breadboard.
I tried it a couple of years ago, but decided to use a newer version of GCC than was in the dox. That didn't go too well, and it was so far into the process that I postponed my efforts indefinitely.
next time I'm going to stick to it and stick to the versions they recommend.