Download RH 8 source file
 

I want to find the RH8 source file ( iso ) to download , but i can't find it at linuxiso and redhat.com , may be it is too old , could suggest where can I find it ? thx.

Google is your friend..

http://linux.ed.ac.uk/linux/redhat-8.0/iso/i386/

Note however that RH 8 was discontinued a few years ago, and assuming you want to be running a current kernel and modern versions of the packages, you would be facing a significant upgrade task if your base system was RH 8. Personally I'd suggest installing a current distro, which in Redhat's case would be Fedora Core 3. Good luck with it either way. -- J.W.