This time of year?........
Have a look at this tent - golite shangrila 3. tipi style tent. just over a kilo packed. make a grounsheet yourself if travelling solo u don't need the whole footprint covered.
http://www.hike-lite.co.uk/Tents/Three+ ... -La+3.htmlI got caught in a typhoon in japan in one and can vouch that it stayed watertight! works well with tent heater too.
Look for things that can serve more than one pupose - a thick foam backprotector in a jacket also makes a usefull section for a sleep mat. Aluminium waterbottle is good - fill it with hot water wrap it in a fleece/jumper/buff/whatever and bung it in sleeping bag before you get in - makes a good hot water bottle.
As mentioned on another post the Heatpal 5100 tent heater is superb and transforms winter camping.
A poncho is handy - very versatile shelter - clip to bike whilst making a trailside brew. makeshift porch on tent .... oh and a poncho too!
Headtorch - one with a red filter - petzl tactikka. headtoch and doubles up as emergency rear light.
Be prepared to get caught out with the short days - a hi viz vest is a sensible addition - mandatory in parts of europe too.
Food! - if your planning to cook your own grub consider a small thermos for a hot drink to keep you going. fill it with hot water before going to bed then in the A.M it requires less heating for the first drink of the day. waterbottles will freeze overnight too!