The installation is highly configurable. Location, JDK can be changed. You can also install the server by itself without Workshop, WLI, WLP etc. IF you missing something in the install then you can catch it in
/bea/weblogic81/common/bin/commEnv.sh or /[DOMAIN_HOME]/[DOMAIN]/startWebLogic.sh
You'll get a dev licence for a year by default. This license limits the number of unique IP's that can connect to your instance of WebLogic to 5. Restart WebLogic to reset the list.