naenae

You are thinking of the Life Cycle series which there are three main sorties starting with Life Renovations and it is by windseeker2305 who you can find on ff.net and there is a link to her yahoo group page. This is the link to the first story http://www.fanfiction.net/s/3991955/1/Life-Renovations

Ok this might be a long shot considering how long it has been since I read the fic. It is a crossover where Spike goes crazy and kills everyone in good ole SunnyD except for Buffy though she is badly injured (i.e walks with a limp, has trouble eating big meals, ect.) I cannot remember how she ended up at Hogwarts but she is there teaching DADA with a OMC professor and if I remember correctly he also makes his own backup wands and is a "yank". Other things I remember is there was a uproar over here being the main teacher because of her age and noone except a few people knowing she was the slayer and fought the muggle way to get people off her back; I believe it was a Snape romance but I can't rightly remember. I am hoping I am not combining two stories together since I have read a few like this on FF.net eventhough that was the first place I saw this one but it doesn't seem to be there anymore.

And I forgot the 'e' on Unlikely *holds head down in shame*

It is not complete but there are 57 chapters here on AFF. The story is called Unlikly Heroes by KusanoSakura the url is http://hp.adult-fanfiction.org/story.php?no=600095300. I followed the author over here from ff.net and has more stories on her livejournel.