do you mean culturing plant cells in vitro? in vitro usually refers to culturing cells or tissues, not the whole organism. From what I understand, most in vitro plant propogation is pretty hard to do unless you supply stuff like plant hormones (see this article http://www.kew.org.uk/science/micropropagation/bgmn84.html). We do plant work in the lab where I work- hydroponic-type and they're hard enough to get to grow right with perfect climate control photo-period etc. in vitro would be that much harder. Sounds to me like it'd only be worth it for particularly rare plant species. Good luck, though, if you're trying it.
I do it's how I make a living. Although I now propagate trees in-vitro a have experience with orchids and some other genera. Alot of plants can be propagated via rooting with a little IBA or by layering.
Let me know what plant you want to work with and I'll see if I can steer you in the right direction.
There are kitchen tissue culture kits available on the web for a somewhat modest sum, but I understand that keeping a sterile environment to prevent bacteria from overtaking your TC setups can be hard . . . but possible.
Since Tim is our resident expert here, I'll see what nuggets he throws out. Firsthand knowledge is often far better! 8)