http://www.travelinescotland.com/cms/Travelbybike.xhtml has a really comprehensive list of transport providers – bus, rail, ferry – that offer bike carrying facilities.
http://www.scotrail.co.uk/content/cycle-rescue.html operates an excellent cycle rescue scheme where cyclists who hold a valid rail ticket, but cannot reach their destination because of accident, vandalism or irreparable breakdown, will be transported to the nearest ScotRail-served station.
http://www.ramblers.org.uk/info/britain/public-transport-for-walkers.htm is a really useful leaflet with details of public transport services for walkers throughout the country.
Check also with relevant local authority and tourist information centres for details on public transport initiatives – including bike-carrying buses – in that area.
Use http://www.traveline.org.uk and http://www.transportdirect.info for route options and times.