Most of the internal items that you would use, such as employee time sheets etc., just purchase generic ones.
The rest depends on your volume. If you send out business cards with every sale, then it will be cheaper for you to purchase them through a printer in lots of 1,000 at a time.
Anything that you need in quantity that is being given to the public, have it done at a local print shop or Staples.
If you are doing flyers or brochures, check with several local printers (small guys). What they will often do, depending on the size of your run, is purchase the paper as a job lot. That would be paper that was off spec for a specific job that might be ideal for your purposes. That could save you 30% of the total cost alone.
If you can get away with 2-colour rather than 4-colour, you will save a fortune as well.
If you are getting your work all done by a modern print shop with laser printers you may find yourself paying top dollar. The end product may be excellent but how much business will it generate for you in the end, that is the question you should be asking yourself.
In otherwords, its ok to spend $1 so long as it returns $5 to you. If you spend $1 only because you want to see your business name printed everywhere, well its not the most profitable way to run a business.
Malcolm