Click here for information about getting to Bath
There is a great choice of accomodation in Bath. It is mostly excellent but can be expensive as supply doesn't really meet demand
Remember Bath is surounded by hills and so if you have difficulty walking it will be wise to check your accomodation is close to the centre.
The differences between these classes of accomodation are blurring. Some guest houses are more akin to hotels offering superb service.
See here for a comprehensive impartial tourist office list. Remember that accommodation providers will need to pay a commision from your booking tot he tourist office.
For a guest house - consider using the Bath Guest House Assocaion's clever site
Self catering can be an excellent option in Bath - even for just a few nights - Bath Self Catering Association is a useful site
Tripadvisor is helpful to many people. Remember that any odd looking extremely positive views or extreme negative views tend to be far less meaningful than the overal picture you get. Sally Lunn's deals with thousands of visitors and the odd few are, well... eccentric and impossible to please. We do get things wrong (as everyone does) but sensible guests speak to us and not vent their spleen on Tripadvisor!) Caveat emptor.....
Stonehenge is very high up on most people's 'things to see' list - a small family run firm do highly regarded 3 hour mini coach excursions leaving central Bath at 10am and 2pm daily. see www.scarpertours.com