The signal for SDI and HD-SDI run over coax cable, RG-59. You need to consider how the camera will be powered.
When running cable for CCTV often purchased is a "Siamese cable" that has two cables bonded together: an RG-59 coax for the video signal and an 18 or 16 gauge, 2 conductor cable for power (marked as 18/2 or 16/2 as in gauge/# of conductors in cable).
The kits come with a 100' cable for every camera with the ends already on them. It's all a kit package and everything you need except a monitor.