http://www.rangerink.com/videos/videos_tim_alcoholinks.htm If the link works ok it will take you to a video by Tim Holtz useing the Alcohol inks but if you don't want to go to the expense of buying try using any permanent marker (peeloff pens) and rubbing alcohol on a piece of felt. The result is not the same but still makes a lovely back ground I'm quite pleased with theses and will use them, what you do have to remember when stamping onto alcohol backgrounds not use stazon because that is also alcohol based it could react and ruin what you have done, use an oil based ink such as archival or versafine.
Since writing this post the ProMarkers have become very popular and work well too