Partyin last night at my homies house boat, and this kid kicks my bong over breaking the inner stem. You can get replacements for that though cant you?
If the stem is all that broke then you're lucky, you can fix it. Did you pull the broken stem out of your bong yet? If you did, then the rubber piece is probably still on your bong (it's hard to get off). You can buy a slide at any headshop .. just make sure it fits. You might want to bring your bong with you (after you give it a GOOD cleaning) - but I don't know if they would allow that. You should just go to the same store that you bought the bong from to get the stem, because they will definately have the size you need. A new stem will probably be about $15-$20.