First of all ---- no one has asked, what size holes are we talking about? and secondly what type of hole saw are you using and what type of drill are you using? If the drill is junk and the hole saws are cheap chinese garbage you will get bad results.
Anything over 1.5" in diameter you can use the hole saws pretty nicely:
Try the Lennox Brand Search LENNOX- They have many kits available with all the sizes, bits and arbors needed
If your are doing holes 1" or less trying using hole PUNCHES by Greenlee search GREENLEE - They have a basic hole punch kits that does great for small holes.
