macbook wireless internet problem... please help!?

[soft rockstar]

Yesterday I bought a macbook. At home, before I purchased the macbook, i already had an imac desktop but it was connected to the d-link wireless router with an ethernet cable. We also have a PS3 that is connected wirelessly to the d-link router. I was able to connect the macbook to the wireless network easily enough, and it works, but sometimes (quite often) when trying to navigate between pages, the wireless internet seems to stop working. It won't load the next page. When i click the "air port" link on the top right of the screen... it always says that "airport is scanning" for a couple of seconds, and then it will say "air port on". The only thing that seems to fix the problem is to go into "network preferences" and reconnect to our wireless router. It will fix the problem for a couple of minutes... and then the same thing all over again. I DON'T KNOW HOW TO FIX THIS? Should I phone apple?