Auto-leveling is not hard (though it is annoying to set up), but the exact procedure varies a lot based on your print surface(s) and what kind of fiddling you are willing to tolerate. There is a lot of misinformation out there, especially on the typical industrial proximity sensors... One thing is for sure however, it will completely change the way you use your printer, and it is definitely worth putting effort into getting it working.
Tom's video (
http://www.youtube.com/watch?v=EcGFLwj0pnA) is the best source of information out there, but even he does not tell the whole story. The method he suggests to connect the sensor did not work for me, most likely because I am not using a Ramps board. Someone else started
a thread on auto-leveling and I replied back when I did not have it working, I will go back and update it for the benefit of others (and you as well!).
I currently use a 18mm capacitive proximity sensor, and my bed is made of a 3mm aluminium block with a 3mm sheet of borosilicate glass on top. Capacitive sensors are supposedly unreliable since they are affected by air humidity and other factors, but in practice it makes no difference for me. I could just be lucky... Inductive sensors are better, but only detect metal surfaces. I have a servo-based solution ready to install (a microswitch at the end of a probe that extends when leveling and retracts once completed), this would make the leveling consistent and work with all printing surfaces with zero adjustment. I'm still debating whether or not I change printing surfaces often enough to warrant the effort.
Cheers,
Ben.