clamd is in the clamav-server package. You could have found this out by yourself with:
$ yum provides clamd
Searching Packages:
Setting up repositories
Reading repository metadata in from local files
Importing Additional filelist information for packages


clamav-server.i386 0.87.1-1.fc4 extras
Matched from:
/etc/clamd.d
/usr/share/doc/clamav-server-0.87.1/clamd.conf
/usr/share/doc/clamav-server-0.87.1/clamd.init
/usr/share/doc/clamav-server-0.87.1/clamd.sysconfig
/usr/share/doc/clamav-server-0.87.1/clamd.logrotate
/usr/share/clamav/clamd-wrapper
/etc/rc.d/init.d/clamd-wrapper
/usr/share/man/man8/clamd.8.gz
/usr/sbin/clamd