It's located at the Veterans Stadium right near the Long Beach Airport. Parking is free and the entrance fee (at the time of this post) is $5 after 6:30am. $10 between 5:30-6:30am.
I encourage you to bring a rolling market cart for your wares for sure. There's a lot of ground to cover. Also, even though there is a concession stand to buy water (and beer and hot dogs and pretzels etc) I'd bring my own water next time. The concession stand is in the far back of the lot.
Another recommendation for those looking for furniture pieces....consider bringing a flat bed dolly. Most vendors will help you to your car but I experienced several that were a little tweaked when I asked.
I look forward to going back for sure!
Find more information on the Long Beach Antique Market here.