airport stopped finding my wireless internet

My macbook pro suddenly stopped finding my internet connection.
It sees the linksys but than says The computer was unable to join.. you may have entered incorrect password or network name or out of range.
Nothing changed from on minute to the next. It was working than it wasn't.
My other mac book is working fine

First thing I'd do is rename your wireless something other than Linksys. I turned on my wireless card to scan for wifi nodes on a drive home a while back - in about 15 miles, I passed nearly 600 wireless networks, and at the time half were named Linksys. If you're in a close community, such as a dorm or apartment building, you may very well be seeing someone else's network also named Linksys.