There are good agents, and bad agents!
Two good agents in my area of West Yorkshire both give floor plans, room sizes and lots of photos on their websites.
Use rightmove to find an area that you are interested in and then see who the local agents are. You will get much better information and better service direct from the agents' websites. They are desparate for business right now. However, as has been posted before, real estate agents are nothing like as full on as in the US - here, they work on much smaller commissions (as low as 2% of sale price). It's not unusual to have the homeowner show you round a property rather than the agent.