If you want access to the member ranges (Practical Pistol Bays, High Power Rifle Range etc.) for practice, you have to be a member and get sign-off by the appropriate Division Directors to document safe completion of a certain number of matches. The TNS Division Director (Dan Coon) will sign off on the Pistol Bay access and the 3-Gun Division Director (Ron Aschenbach) will sign off on High Power access once you successfully complete a number of their respective matches.
I am the 3-Gun Match Director. You can shoot in my match, but first timers have to attend our New Shooter Orientation on the morning of the match. Watch this website (ARFCOM AZ Hometown Forum) and you will see that I post details of all Rio Salado 3-Gun/Action Long Gun matches each month. If you want to be on our email list, send me an Instant Message or Email Message with your name and email address, and I will make sure you receive our match updates.
As for whether membership is worthwhile, that entirely depends on how much you shoot, and at what. Members enjoy preferential pricing on match entry fees and clay shooting. The real value lies in the ability to shoot at the range whenever you like for free. The range is very busy at weekends, but on weekdays you can usually have a bay to yourself (once you get access privileges, of course). My annual family membership costs less than one months satellite TV bill, so I guess it all depends on your priorities.
I look forward to seeing you at our October match.