Dreamhost operates under suexec, which allows scripts to run as your user instead of the webserver's user. This obviates the need for a dedicated cgi-bin, as you can run scripts from any directory with permission set to 755 for the directory and the script. If it makes your xfer of sites easier, just make your own cgi-bin directory, and set it to 755 permissions.
All Dreamhost accounts come with ssh access available at no additional cost, but the user must be shell-enabled in the Control Panel for them to access the shell via SSH.
The following DH Wiki links should help explain some of these issues for you:
CGI, PHP, and Databases