Learning to groom at home is very rewarding.
Here is a thread about the leading clipper brands:
http://www.yorkietalk.com/forums/yor...-clippers.html
My boys are in full coat, so I cannot advise on puppy cuts.
Grooming when your dog is relaxed is a good idea. Take your time and work with confidence. Dogs tend to react to anxiety. You already have experience with scissors around the face, so you and your dog should be just fine. Good luck!