I understand what you are saying and what you are asking. Once you have the compiler installed, the answer will be yes, you can just download a source code file of the form package.tar.gz, then unzip it, un-tar it, and them issue the commands
That tells the compiler to compile the source code into machine language that the computer can execute directly.
Unfortunately, you don't yet have a compiler installed. That is what you are trying to do, so you can't compile your compiler from source code....exasperating, huh?
The next step up in simplicity is to download a package of the form package.rpm and use the rpm command to install it. rpm's are already compiled. Unfortunately, they don't contain all of the source code necessary to get the application running. People use rpms to break all the code of the computer into pieces for easier handling and to avoid duplication of code/effort. The rpm lists the other pieces of code they need to talk to in order to get the application working. These pieces are other rpm files called dependencies, as the one rpm depends on the other. The rpm command tells you what other rpms it needs, and you have to find them download them, and install them in the order necessary so that all dependencies are met sequentially.
Package management systems, like yum, were made to ease this burden. The entire collection of all rpms, the whole "web" of them that has to hang together, is stored in one place called a repository, hosted on some web server. yum has access to all of the rpms, and all the rpms describe their dependencies, so yum can figure out which rpms it needs to install the application you want, and the order they have to be installed in, and then does all this for you. Without package management, life is tough and you become a book-keeping accountant and scrounger looking for rpms, as you have noticed.
There is a file associated with yum that tells it where to find this repository on the internet. The link in post 16 shows what the entries should look like if you want to use the free centos repository, which is a blatant copy of the red hat network one that Red Hat won't let you use without paying them a subscription fee.
I hope this is beginning to make sense. keep posting here or on the centos forums.
As one person has said...you wouldn't have to even change the yum repository file if you are not too far into RHEL yet and would just instead install Centos 5 at the outset. It is a 100% copy of RHEL 5 without the red hat name (trademarked) and the red fedora man logo.
It is up to you...change the yum repository file as in post 16 link, or just download, burn and install centos 5 and be done with it.
you can even use a net-installer within windows to download centos, as well as many other linux distributions:
you just download it if you are dual booting windows, open it like any other wizard installation app, and let it do the rest of the linux dual booting installation.
Otherwise download and burn a cd of centos5 and install it...it is actually up to 5.1 now.
keep posting...we want to help you.