Okay, you wanna be a mechanic. This is not an easy process. It takes time, time and more time. The first thing you should know is most people won't show you and most of the literature out there on base dealing or dealing seconds, strike seconds and greeks is incomplete. The only book you should think of getting is "The expert at the card table" be Erdnase. If you want to spot base dealers you will have to learn the different types of "grips" that magicians and mechanics use. If you can spot the grips you can spot the cheats.
My Advice for those without the gnosticism
Okay, I hope you have seen the move "rounders" and you know what I mean when I say a "hanger". If you don't know what a hanger is, its when the second card from the bottom also comes out a bit when someone is base dealing. This does not happen when someone is dealing from the top of the deck. If you see a hanger, grap the f@*cker by the wrist and check the cards, the bottom of the deck and the person he dealt to when you saw the hanger. Next beat the living crap out of the guy. I'm serious. Beat him into an inch of life. Cheating is not cool. Or send him to my home game and I'll show him what cheating is.
More on Base Dealing.
Base dealing is probably the easiest of sleight that someone can learn, Ergo there are a lot of sloppy base dealers out there. I literally spent years trying to perfect my sleights(Which i use for entertainment purposes only, It is a great way to win free drinks at bars and to pick up chicks. Little kids also love card tricks) The best methods for base dealing involve using your middle finger, on your card dealing hand(not the one holding the deck). It passus through and your fingers on your gripping hand and lightly slides the bottom card off. With skilled mechanics the finger is shaded by your index and middle finger of your gripping hand. as the two fingers will be near the front right corner(for righties) of the deck. If you okk closely you will notice that the deck is actually gripped with the left index finger on the front of the card deck and pinched withe the pinky finger. your other two fingers are on the inside of your gripping hand and may appear to be more extended than a natural grip. This is beccause this is where the card must come out from. This is the most common grip for base dealing. More advanced sleight experts and cheats will put there pinky finger at the side with the rest of the fingers while pinching the deckl with the palm (in the nook by the thumb)
Pay attention to the sound of the cards. The sound of a carrd coming off the top sounds different than the sound of a card coming off the bottom. If you don't believe try it yourself. I know it can be hard to hear at a card table sometimes but you will have train yourself to pay attention during the deal.
My final Word
Being an expert a sleight of hand is a painstaking process, but there are a lot of people who use this knowledge to cheat us out of our money. If you haven't seen the movie "Shade" i would recommend renting it as the opening and end sequences show experts dealing, but the view is from underneath the table(They are doing over glass) This is some pretty amazing stuff and if you have a keen eye you should be able to pick up on things that you should be looking for in questionable games. But hey folks cards are like the Jedi and the Force, there is a light side and a dark side. This should always be foremost in your mind when playing. And remember 50% of people will cheat if the opportunity arises, so if you aren't cheating, then the other guy probably is.
For anyone else who has more questions on cheating and cheaters please feel free to pm me or email me as I am more than happy to discuss this subject at length and i wouldn't worry so much about base dealing as i would worry about marking and marked cards as this takes a lot less skill to pull of.