I'll answer your second query since I know nothing about the first.
In order to become a supplier, you first need to know and or choose what type of products you wish to supply to locksmiths, what locksmiths you wish to supply to, and of course, who is already supplying product to them.
You then need to decide how much you are willing to invest into such a business.
Basically, it's market research first.
Once you've done that, you then need to find companies (preferrably the actual manufacturers of tools, etc.) and contact them in regards to their process in becoming a dealer.
Different companies have different requirements, and some have minimum amounts that you need to purchase and/or minimum sales requirements. Some also will not do business with you if you are selling competitors products, so keep this in mind as well.
You also need to decide how you will market these goods and what kind of profit you will require to be successful.
Licensing, legal issues, and many other things will have to be considered as well.
It is NOT just a simple matter of phoning up HPC or Southord and saying, "I'll take $5 GR at wholesale prices so I can resell it.".
Do your homework, and shop around.
I think I may be interested in being a Locksmith supplier and I was wondering if anyone had any info on that. Maybe like a site that sells bulk wholsale tools and equipment or maybe a site that lets me sell through them. Or just any hints on where to start.