def not trying to be hard on you, but this question gets asked once every three days. do a search on this site, or google it. TONS of resouces out there that walk you thru the basic setup process.
some starter info...
samba is included with nearly every distro... go to the add./remove applet in Redhat and make sure you installed it. the install directory may vary based on the distribution.
run a search for smb.conf on you whole hard drive.
advice: consider using the webmin tool (www.webmin.com
) to configure samba and samba users (different that linux system users - very imp!). also look into using SWAT (samba web administration tool), a html based util for configuring the service, starting and stopping it, etc.