Go to System Preferences/Network. Select Airport and then click Configure. Select Automatic if it isn't the default selection. Click "Show Airport status in Finder menu Bar" for easy access to Airport and connection status info.
When you go to the "Internet park" and Airport is active then you should see the free network is available as a choice in the Finder Menu Bar drop-down menu when you click the Airport status icon. Select the network to connect to it if Airport doesn't connect automatically.
But also be aware that senstitive log-in and other data will be transferred in the clear unless the network is password-protected and encrypted, which is unlikely. Such data can be easily grabbed by someone monitoring the wireless network. (The same is true for wired networks in hotels and similar locations.)
It is very important to use a VPN connection when using public wireless networks. PublicVPN is inexpensive and easy to set-up (
http://publicvpn.com/). A more secure alternative is personalVPN (
http://www.witopia.net/personalmore.html) which is less expensive but you have to sign-up for a year and activation may take 1-2 days.
You could go with PublicVPN for a month which is around $6 and be able to go online as soon as you configure the VPN settings that are part of 10.4.
Be sure to connect via VPN before starting up your e-mail program and Web browser.
I have used both services and now I use personalVPN exclusively. Using VPN will slow down your Internet connection, but personalVPN has speeded up considerably since I began using it and its download speed is quite acceptable to me. An added bonus is that your IP address is not traceable to your computer and your regular ISP cannot see where you are surfing or read the data being transferred since it is encrypted.