How do I wirelessly connect my macbook to my linksys router.?

I have a WRT160N router and I have installed it and I even configured it on the website however Every time I try to connect to the network, it says connection timeout. I even used the network diagnostics a hundred times but it just says this computer was unable to join the airport network you have selected. I use WPA and I use the correct pword but it still doesn't work. I even tried connecting without security but it still doesn't connect. Please help!!!