SBA Controller; distracted by automated hand-off problems with ZOA; permitted two IFR arrivals to conflict while being vectored for an approach.

Narrative

An AA5 was on a downwind vector for sequence RNAV 29 Approach. Preceding the AA5 was a C310 IFR descending on a visual approach straight-in to Runway 29 at SBP. I answered a land line call due to an F16; VFR overflight. The call was from ZLA Sector 15 whom took the automated hand-off on the F16. The F16 should have defaulted to ZOA Sector 10 on the automation. After I got off the line with ZLA 15; I called ZOA 10 for a hand-off on the F18 indicating 480 knots. That's when I observed the AA5's proximity to the C310 and turned the AA5 30 degrees right. Recommendation: resolve automation problems between SBA TRACON and Oakland Center. Many times we cannot affect automated hand-offs without tricking the NAS (National Airspace System) via FDIO (Flight Data Input/Output) amendments. i.e.: amending VFR altitudes requested above Oakland's shelf airspace; to an altitude below shelf airspace knowing that aircraft performance will not allow aircraft to top Oakland's airspace. Amending an IFR altitude of departures off SBP going to ZOA's airspace with 80/PRB/240... This altitude amendment will allow SBA TRACON to affect an automated hand-off with ZOA. If automation could be used in lieu of non-automation; our workload could be greatly reduced.