Hi Romulo,
If you are talking about just code samples of how to access postgresql I can help you with that for sure. If you are asking if you can use the server explorer in VS 2003 like you can with MS SQL I think the answer is no though I have never tried it.
To access postgresql from code you will need to use the npgsql provider which you can find here
http://gborg.postgresql.org/project/npgsql/projdisplay.phpI will email you a class file containing a lot of example code that uses npgsql to access postgresql.
Hope that helps,
Joe