Anime-Beta TNG

I had been more involved with cels a few years back but I had went to look at my cels the other day and noticed the black paper, from the cel book I had bought for them, were sticking to some of them.

They weren't in cel bags but I got some now. But how should I go about separating them without damage?

This is where i got the cel book
http://www.darkharbor.com/trades/html/celbooks.html

I would take a clean towel (or Q-tips) and use it to dab some water on the paper where it is stuck to the cel. Once the paper is soft, it should come off the cel without damaging the paint. The trick is to make sure that the paper is wet enough that it tears/comes apart while the paint stays on the cel. Of course it will ruin the paper, but that's not a big deal in your case. It would be a problem if it was a nice sketch that was stuck.