bug.co.uk
uktrail.com
http://www.kayak.com/hotelowner
http://www.travelpost.com/help/hotelowner.html
Yahoo Travel: http://help.yahoo.com/l/us/yahoo/travel/submit/ (not just Yahoo Local)
yell.com (UK)
UK Yahoo Local http://uk.local.yahoo.com/ (UK and Ireland)
http://www.merchantcircle.com/
This one isn't free, it's $30, but worth it:
http://www.universalbusinesslisting.org/
http://www.nileguide.com/destination/munich/hotels/wombats-city-hostel-munich/1393712