I agree with Rifleman. This pistols are not that complicated, although the many small parts can be intimidating at first. Tuning up your fist 1851 or Walker is kind of liberating and fun.
I found these two YouTube videos very helpful before attempting my first full disassembly; it help in understanding where all the parts go. http://www.youtube.com/watch?v=Au-d3SbELvQ
I occasionally refer back to these videos as a refresher before diving in!