There is no one method to get ALL database servers. Each is going to have it's own method that you're going to have to use. You've already found SQL Server's, now you have to use a library specific to Oracle to get it's list. There is no such thing as an OleDb database server since this is a relatively generic method of access them. If you're refering to MySQL Servers, you'll have to use a library specific to MySQL to get it's server list.
A guide to posting questions on CodeProject[^]
Dave Kreskowiak Microsoft MVP Visual Developer - Visual Basic
2006, 2007, 2008