re accomodation - I can only suggest trying the gov tourist site (off www.gov.im)who can provide some guidance - or look at advertisers on this website (see tourism tab above) - having my own place means I havn't needed to organise accomodation for many years.
If you are planning to work in Museum then accomodation in Douglas within walking distance would be more convenient - parking in Douglas is inconvenient and/or expensive - the bus takes some 40mins from Peel, 1hr from Ballaugh. You will need a car or be prepared to walk to get to most of locations connected with the familes you mention.