Hi SASPhile,
I took the following in-class course "https://support.sas.com/edu/schedules.html?id=89&ctry=US" and learned a ton from it.
Even if you take the class I recommend reading up on the subject beforehand, because it moves very quickly. I studied the 4-volume SAS/ETS user's guide (http://www.okstate.edu/sas/v8/saspdf/ets/pdfidx.htm), but mostly just the ARIMA procedure.
I also found the book Time Series by Kendall & Ord at the municipal library, which explains the theory behind time series analysis. In my limited experience I've found that there's as much art as there is science to time series analysis, and theory helps explain some of the choices that need to be made, more so than the SAS User's Guide did.
Good luck and happy learning!
Tricia