Get out your Samsung user manual
Go to 'Phonebook' > 'Options', then scroll down the contact list. Now hit 'Save to SIM'
In addition to that, simply upload all your contacts to the cloud somewhere, this way you won't have to be as worried about accidentally losing them when you switch handsets/cut the SIM down to fit, etc. It might mean backing up your SIM with a SIM adapter for your PC, and/or using the awful Samsung PC Suite software. YMMV. I'll be honest though, once you get your contacts into google, there's a heck of a lot of flexibility in getting them onto your i-Device.
Visit howardforums.com for more concrete details as well. It's a very helpful site.