You can set up virtual hosts (any number you want) within httpd.conf or use Fedora's GUI admin tool for HTTPD. Virtual hosts can be IP or name-based. In your case name-based is the reasonable choice, because you have a single incoming IP with your DSL account (I suppose so).
Apache.org has proper documentation on virtual hosts. At the basic level it's quite trivial to do, a matter of a few minutes.
You need to register your domain names with your DSL's IP number assigned to the registration. For test purposes simply add your test domain names into /etc/hosts with localhost or 127.0.0.1 as the target IP.