30 every 3 years. I think I am at about 55 from the past two years towards my next re-up. they are pretty easy to get.
The online seminars that G posted about a number of times are good and free, the ones from the ISA magazine are also easy, and paid for with your ISA membership. Hit a seminar or have some documented tailgate safety meetings and you could be able to get them.
If pressed for time order up the CEU compendium and fill in the quiz sheets.