I am doing some 2 for 1 transactions, and when the people that requested them sent me a PM with the book they requested, I deleted it from my bookshelf, so that it would stay up to date for other requests. 

Now I am working on sending them out, and would like to use PBS postage.  I know that the additional book will mean additional postage and I need to adjust the weight before printing the wrapper.  How do I find out how much the additional book weighs in order to get the correct postage on the label? 

Thanks in advance!

Is there anyone who can help me? I want to get these out today!

If you don't have a scale, then I would just double the weight and add a little extra assuming the 2nd book is the same size as the first.

You could try looking up the weight of the second book in the listings, but be aware that PBS weights aren't always accurate.  Without access to a scale the best you can do is estimate.

I asked the same question last night and was told by a "seasoned swapper" that if the books are about the same size, just double the weight in the weight box (I can't remember exactly what it's called, but I just did it!), and it will figure it for you.  It doesn't double the price, it only goes up 30-40 cents (depending on # of books, size, etc.) and on you go!  At least I hope so.  I've put it in the box, ready to go!