What a great draw, first time we've played in Lincoln since 1998 (if my memory serves me right). The Lincoln massive will be there in force!
There are a few pubs within walking distance of the ground, mainly on the south end of the High Street (Golden Eagle, Shakespeare, George & Dragon, Millers Arms, Golden Cross (pretty rough). Some of those mentioned by Diego like the Strugglers are good pubs but a long walk from the ground. The Ritz (Wetherspoons) is about 10-15 mins walk from the ground, but after a pretty feisty altercation between Lincoln and Grimsby fans (yes Lincolnshire has a derby!) a few years back I'm not sure how footy fan friendly it is.
As someone else has mentioned the Christmas market is that same weekend. Its now supposedly the biggest in the UK, of not in Europe, so hotel prices if you can find one will be sky high.