Most local fish stores carry Safe Start (or could order it in for you), though I have never seen it in any of the chain stores with the exception of Aquarium Adventure, which is a part of the Petland chain. Bio-Spira is much harder to find. A few others have had success with Seachem's Stability or
API StressZyme though most say these products are not all that reliable. I've read very few good things about Cycle but the occasional person wil say they have had success. These last three products are usually available at all the chain per stores.
You can definitely mail order Bio-Spira or Safe Start though shipping is usually expensive as the ship it refrigerated.
In any event, none of these products should hurt your aquarium and may provide a bit of a boost in generation your biological filtration, though Safe Start and Bio-Spira will be the best.
John