1 year Libor plus 350 Basis points = what interest rate today.

Libor's available in assorted flavors, so you'll need to know which specific variant your loan agreement is pegged to. For current rates, check here
FT.com - Markets Data - Overview

Bottom of the page; select: Choose a category = Bonds & Rates; then Choose a report = Markets Interest Summary. Then click on the most recent day available from the calendar.