Try this:
IF EXISTS (SELECT name FROM sysobjecs WHERE id = object_id(N'tablename')
AND OBJECTPROPERTY(id, N'IsUserTable') = 1)
SELECT * FROM tablename
Or to get a list of tables (using this query in the EXISTS clause above also works), this is even easier:
SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES
"Well, I wouldn't say I've been missing it, Bob." - Peter Gibbons