The mind's eye will help you pick more than your visual senses.
As landeroth said, and as many here will agree, a cutaway lock is a great way for first timers to have those "aha" moments where it clicks and you understand how a lock works, what a key pin is, how a shear line works, what binding order means, but for picking practice, it's more of a pain to try to hold a cutaway, pick it, and look at it at the same time. If you take some locks apart and put them back together, this will build up your ability to visualize how the parts interact with each other while your pick is moving inside the lock. You'll be able to visualize distances and forces needed for the pins to be moved, as well as how much torque to apply to the wrench. This skill will come with time and practice, don't get discouraged if you dont have this "X-ray" vision in the first month of picking locks, most of the time, they will just seem to open with a mixture of skill and random luck.
digital_blue's exercises posted somewhere around here will show you how to take a lock apart and pin it back up pin by pin and build up your senses and skill level.
Welcome to the greatest hobby you'll ever be a part of.