We have a username and password that is used for all employees so we have access to almost all ASTM standards, as well as the other free ones too. Not sure what the cost of the subscription service is though. Hope this helps.
My company also subscribes to this service. It is quite thorough, but quite costly as well-- full access to the entire ASTM collection runs about $10,000 (US currency) per year.
There is a complete set of all 72 ASTM volumes dated 1998, including the index, for sale on eBay. Item # 3515288209.
Minimum bid is $990 (shipping & handling to be added).
Getting all the volumes would be interesting, but then as time progresses you need the revisions anyways.
My former company has an online subscription to some company that can get you a wide variety of specs. I'll get the name of this company and post it when I find out.