That is a great question. It's important to make sure you're getting the best bang for your buck when recycling your old LCDs.
iFixit Pro (iFixit's solution for Repair Businesses) just launched the iFixit LCD Buyback Program. You can learn more about that at pro.ifixit.com. Prices are very competitive from what I have been comparing around the internet.
I'd also recommend joining the iFixit Pro program, if you aren't already involved, to gain access to a wealth of knowledge from other techs. There was recently a discussion about just this topic on our Pro Talk forum.
Check it out at pro.ifixit.com