Don't mean to undermine turexy-exp. Again, if it's not default settings, you can query the java process that weblogic is running by running
ps -ef | grep java
You can find which port Weblogic instance is running on by examining it with pfiles.
pfiles
| egrep -i "sock|port"
If you are running linux, you can get pfiles at http://sourceware.org/systemtap/wiki/WSPfiles
Once you found the port, check out which interface it's binding to via
netstat -an | grep
Then, like turexy-exp said, you can access it via http://ip:port/console