Debdon, we got our visa through China Holidays in London. They cost £45 including admin charge. Link to the appropriate page on their website is here - http://www.chinese-visas.co.uk/
Vaccinations - during the appointment with the nurse he/she will ask him which areas he's going to, check his records to see which immunisations are up to date and then tell him if he needs anything additional. Here's a link with more info - http://www.netdoctor.co.uk/travel/asia/china.shtml
Most of ours where up to date anyway and the additional ones we needed were free.

Thank you puddleduck2 for all that info, it is exactly what we needed. You are a star.

Hi, Doing a China tour with Archers in June. Have had all the usual vacs, but have heard that as our trip includes a Yangtze River Cruise we should take malaria tablets with us. Any info on this? Thanks

Hi Alan, you can look on that net doctor link I gave Debdon above for malaria advice.