I've finally reached the point where I'm getting rid of 2/3 of my vinyl collection (1,000+ LPs) for the same reason - no space, too many CDs, and more and more MP3s to keep track of.
I'm not selling them here or anywhere else, but hope to have a buyer from Amoeba come by and take them off my hands for trade value. I spent the day sifting through them and was as ruthless as I could be. I still have somewhere around 400, but the situation will be MUCH more manageable from this point on.
A very "painful" task, but necessary.