Where is the memory card on the Samsung Stratosphere?
Remove back cover and you will see the card located in the right hand side corner, simply press the card and it will pop out to be removed.
And just a word of caution: before you take out the card, you might want to do (from the Home screen) Menu > Settings > SD card & phone storage > Unmount SD card. I don't know what happens if you don't do this procedure, but why take a chance? It sounds sort of like the "Safely remove hardware" procedure for USB devices in Windows.
That;s a good ideal but mostly all the new devices are hot swappable and usually dismounting isn't needed,