query help for a noob

[rich banke]

Hello, I am just starting to learn how to interact with mysql. This seems like a very simple query however all the examples ive seen just dont seem to work out for me. Here is my problem, I have 2 tables each with a column named 'charname' table1 is a complete list of users, table2 is a list of currently online users. I want to run a query that will tell me which users in table2.charname are also in table1.charname. I have tried several ways of using a left join and the only results i have been able to retrieve is a complete list in table1.

'select table1.charname from table1 left outer join table2 on table1.charname = table2.charname where table2.charname is null'

this is only 1 of the examples ive tried.
thanks for any help
-Rich