There are many instrument drivers available at the link below.
http://zone.ni.com/idnet/
If you find an IVI TDS3000 instrument driver, you can call it from Visual Basic. The link below describes how to do it.
http://ae.natinst.com/operations/ae/public.nsf/fca7838c4500dc10862567a100753500/ceecfcbf5015ab6f862568a100640eb0?OpenDocument
Kim L.
Applications Engineer
National Instruments