Dude, it doesn't sound like you've got gcc installed.
1. If you really think "gcc" is somewhere on your system, you can search for it with a brute-force method like this:
find / -name gcc -print 2>/dev/null
2. The "/usr/gcc/gcc-3.0.4" you downloaded is apparently a *source* distribution. In other words, you need to build it. And of course, you can't build it (or anything else) without an existing compiler.
3. The *easiest* approach is to just download a binary gcc RPM. For example:
'Hope that helps .. PSM