First, @MarkusWeick is totally correct - Arrays aren't tested until the Advanced Programming Professional A00-232 exam. If you are seeing references to it being part of Base, run away (quickly!) from whatever source you are looking at - it is out of date by something like 5 years. Head to SAS Global Certification | SAS for accurate information.
That being said, if you are just interested in SAS arrays (and you should be, they are cool, but a bit weird relative to other programming languages. Maybe not the place to start your SAS learning) - Papers from SAS conferences and user group meeting are an excellent reference. -
SAS Proceedings and more (lexjansen.com)
Pop 'arrays' into the search box there and enjoy!