sim cards

were common in cell phones used in europe when I spent alot of time there in the '90s, but my current phone only a few months old is the 1st I've had that has a sim card. Many of the newest phones do have sim cards, but I think a reasonable guess would be that more than 90% of cell phones ever sold in the US did not have sim cards.

For the phones with no adapter, if you want to take the time to do it, there is a good chance you can find one at the local Goodwill, DAV, Salvation Army store, etc.