If the Storm is unlocked, it shouldn't be a problem. If you haven't specifically unlocked it from Verizon though, you'll need to. (It's very unlikely a carrier would sell you an unlocked phone.)
Wireless? I had service through Verizon Wireless and dropped it. I got a Blackberry storm through Verizon, I switched service to US Cellular. Can US Cellular activate my Blackberry storm?
How do you unlock it?
If the Storm is unlocked, it shouldn't be a problem. If you haven't specifically unlocked it from Verizon though, you'll need to. (It's very unlikely a carrier would sell you an unlocked phone.)