i agree with the above, being fairly new to this medium myself.
plus with Tandy, if you buy the kit you get access to their lessons as well - which are a really good starting point
I would also add don't be afraid to make mistakes. When you start what would appear like doing something simple like cutting, you will mess it up. even when i do that i still complete the piece, it teaches you how to do the rest of it, and the key to leatherwork is practice.
Don't be harsh on yourself with critique, when you have finished just ask what could i do better, it might be moving a snap under a piece of leather instead of on top of one. Progress wasn't built on success!
Most of all enjoy it, i find lacing and sewing quite therapeutic (some find it mind numbing). At the end of the day i look at something and say "i made that from scratch", that's the reward
Scoot