Desert Breeze park, on Durango and Twain. There is a kids playground and car park there - usually you can find crazy people running around in garb hitting each other with swords on Saturdays from 12, or a smaller practice on Tuesdays at 6pm.
Great bunch of people who are always willing to help (I know this cos I have only being playing a month and they welcomed me with warmth and enthusiasm...)
Hope to see your cousins at a practice soon
P