
In Thunderbird, click on Tools -> Address Book...

Click on File -> New -> LDAP Directory...

In the General tab, enter in the following information:
Name: CSULB
Hostname: ldap.csulb.edu
Base DN: o=csulb
Port Number: 636
Bind DN: uid=username,o=csulb
Also, make sure to check Use secure connection (SSL).

Click on the Advanced tab and set the Scope to One Level. Next, click OK.

Finally, select CSULB from the Address books and then type in the name you wish to search for.
Thunderbird (MAC)

In Thunderbird, select Thunderbird -> Preferences...

Click on the Composition button at the top, select the Addressing tab and click Edit Directories...

Next, click on the Add button.

Next, fill in the boxes correctly:
Name: CSULB LDAP
Base DN: ldap.csulb.edu
Search Base: o=csulb
Port: 636
Bind DN: uid=username,o=csulb
Also, make sure to check the box labeled Use secure connection (SSL).

Then, select the Advanced tab and set the Scope: to One Level then click OK.
Go to File -> New -> Message.

Next, click on the Contacts button and then select CSULB LDAP from the Address Book: list.

Type in the name of the person you would like to search in the Search For: field and hit Enter.