First..... know what you have on hand... spinnaker type, existing rigging, hardware, etc... do some research so you'll understand the different spin types and how they work.... then learn the nomenclature.... when you've done all this you will be able to make an inventory.... then a shopping list.... After that.... you go shopping at any online chandlery... or ebay... West marine... or what ever method you choose.... used or new....
The point is.... if you don't know what you need and what to look for... you're wasting your time and ours... and more importantly... you'll be wasting money. Start here:
https://en.wikipedia.org/wiki/Spinnaker
Here's a common set up for the pole called the "end for end" rig
Here's an asymmetrical spinnaker set up:
Are you confused yet? Read up on the subject so you'll know what you have and need.