Hi David,
There are some C Code examples for the MSP430F5508 using SPI communication here: http://www.ti.com/litv/zip/slac394c.
We don't have much example code specifically for the ADS1259. You can try seaching the E2E forums for some examples. These threads have some links to related code examples:
http://e2e.ti.com/support/data_converters/precision_data_converters/f/73/t/217076.aspx
http://e2e.ti.com/support/data_converters/precision_data_converters/f/73/p/197313/704459.aspx
Regards,
Chris