Lost in Shinjuku (really!)

I went to the west exit area of Shinjuku station (新宿西口) on the way back to home from university in order to buy the most low-priced set of canalphones.
I buy it almost a month because I listen to music with Gigabeat for many hours a day so my earphones get soon to be out of order.

At first I visited Bic Camera there but was not able to find it. Every set of earphones they had were a little more expensive than ones I wanted.
Next I went to Yodobashi Camera near Bic Camera. There I found canalphones (780 yen) I wanted.
I think that Yodobashi had a better selection than Bic.

By the way I lost my way there today too.
Although I have already lived in Tokyo for 7 years, I often lose my way at the west exit area of Shinjuku and all areas of Shibuya.
I cannot walk around at these places without maps.
I know the way in detail at Asakusa, Ueno, Akihabara, and Ikebukuro.