I have had to call for help today after some people pointed out a dog locked in a car in full sunshine in temperatures in excess of 26/7 degrees. (We were parked in full shade and the temp on our display was reading 24.)
Called the police on 101, they cut me off three times, then put me through to the local branch, who said 'we don't do animals' and told me to call the RSPCA.
Had to Google to get the the RSPCA 'emergency' number and that took what felt like hours, as there was no signal on my phone. When I did get through on the number I was kept waiting for almost 15 minutes listening to them advertising their website and asking for donations while the poor dog suffered. 
Eventually got through and it took a good 10 minutes for them to take my details and those of the dog/location etc. They wanted my address and phone numbers first (after the recorded message said they would use my details to target marketing [hmm). Then they wanted a description of the dog and it's markings and how distressed it looked etc, when I had the car type, colour, distinguishing marks and reg number, plus the location, precisely where it was parked and told them it had been there for at least 50 minutes that I knew of, but the car had been there since I arrived, so in all probability it could have been there even longer.
They said they'd dispatch someone asap, then five minutes later I got a call from the local RSPCA control centre to say they had no-one available ... so had called the police out. Which should have been what happened when I made the first call via 101 and then the dog wouldn't have been in the car for an extra half an hour while they messed me around.
By this time the dog had been in the car for around 50 minutes that I knew of, while I desperately tried to get some help. I wish I could have broken in and got it myself, but I wouldn't know where to start and no-one else wanted to get involved (plus I'd have been done for criminal damage - although if it had saved the dog I'd have lived with that).
We had to drive up the road to get a signal on the mobile and were late to pick up my dcs from school (ds1 has ASD and I can't be late to pick him up from school) so couldn't go back to check on the dog again and don't know when help arrived, if the car was still there when they did or what the outcome was.
It was awful, I felt shaky and sick both with worry for the poor dog and sheer frustration at not being able to get help. I can't believe it survived for that length of times in those temperatures, but am desperately hoping help got there in time.
The ridiculous thing is there is nothing there, just a country walk and small cafe with loads of tables outside where dogs are welcome - so no reason to leave a dog in the car, as there's nowhere to go without it.
What else could/should I have done?