ACCOMMODATION PROVIDERS OFFERING DISCOUNTS FOR GUESTS ARRIVING BY BOOT/BIKE/PUBLIC TRANSPORT:
http://www.green-business.co.uk lists places to stay with criteria for assessing their environmental impact, like energy efficiency, waste minimisation and recycling, use of local produce and support of public transport
http://www.sawdays.co.uk has sections on ethical and green places to stay and information on providers mentions if they are willing to pick up guests from local stations, or if they offer discounts
http://www.doune-knoydart.co.uk collects guests by boat from the pier at Mallaig (visitors cannot take cars on to Knoydart)
http://www.cornwallpublictransport.info/other discounts lists two hotels/guesthouses offering discounts and the site provides comprehensive information on all aspects of public transport in the county
http://www.yha.org.uk Bellever Hostel in Devon offers a discount to anyone arriving by boot/bike/public transport
http://www.thenewforest.co.uk operates a Green Leaf tourist scheme that promotes car-free tourism with some providers offering discounts for guests arriving by boot, bike or public transport
http://www.railholiday.co.uk (self-catering accommodation in converted railway carriages in Cornwall) will give £25 cash back to any guests arriving by public transport, boot or bike
http://www.isleofmull.co.uk The Argyll Arms, Bunessan, Mull, actively welcomes booters and bikers and, although it does not offer discounts, will provide transport to and from ferry ports and does give details of bus connections and other useful information for guests not using cars
http://www.responsibletravel.com and http://www.greentraveller.co.uk have comprehensive lists of green and sustainable accommodation, including those offering discounts, and give details of alternative forms of travel
It is clearly not possible to list any more than a few suggestions of how to find suitable accommodation.
An obvious starting point is to search by location: type where you want to go into Google, or find the relevant tourist information services for that area.
Suggested general sites for the UK:
http://www.britainexpress.com/tic/index.htm lists tourist information centres throughout Britain
http://www.undiscoveredscotland.co.uk has comprehensive information about all areas of Scotland, including an extensive index of accommodation.
For overseas destinations, your best bet is to search online for details of the particular country and/or contact the relevant tourist authority.
Once you have decided on a location, you can search further for accommodation by activity
http://gouk.about.com/od/travelbyinterest/qt/walkerscyclists.htm gives details of the walkers/cyclists welcome scheme, with explanations of what has to be provided to earn the logos. All accommodation listed on the general sites above should display the logos, where appropriate.
In addition, activity-specific sites like:
all have extensive lists of all types of accommodation in Scotland and in some overseas locations.