Referencing created tables fails with message that they do not exist!

I have just installed Postgresql and tried it for the first time.

One very serious problem I ran into was when actually trying to use
created tables.
Creating a simple table without any foreign keys works OK, but after
creating the
table it is not possible to do a select on it! I tried the following
variants:

SELECT * FROM <table>;
SELECT * FROM public.<table>;
SELECT * FROM <schema>.public.<table>;

All result in the message "The relation <table> does not exist!" or "The
relation public.<table> does not exist!".

Creating a new table with a foreign key referencing the first table is
also impossible due to exactly the same error message!

This behaviour is the same using  DBVisualizer/jdbc or psql.

So the question is how do you actually reference the tables you have
created so that postgres will find them ?
The tables do actually get created. I can se them in DBVisualizer.

I'm using version 7.4.5 on Linux Mandrake 10.1.

Best Regards,
Tommy Svensson