The springs are on USFS land so they are free. There are several pools at different temperatures that range from about 90 to 109 degrees depending how close to the source they are.
From Green valley Lake you could come in on the 173 if you don't mind dirt roads. The Bradford ridge trail starts at the little white wooden bridge that is five miles before the pavement. The USFS requires a Forest Adventure pass to park here. This trail takes about an hour ten down, and an hour and a half up and is quite steep when it decends down to Deep Creek.
If you prefer an easier trail you should take the 138 to the 173, and then take the road down to Hesperia, continue east to Bear Valley Road. Make a right on Bear Valley and then another right at Central (the first stop sign). After you go over a small steep hill make a left on Ocotillo, and then a right on Bowen Ranch Road, stay on the right at all forks till you see the welcome sign to Bowen Ranch. Mike charges $4 per person to park on his land. From there the trail is about a forty minute hike down, fifty to an hour up.
Hope you have a good time. Please remember no glass, campfires or overnighting is allowed at the springs. Come back and let us know you it went.