Not sure if this is the right area to post it, but since this is about woodworking and construction and the Lexan overlay is needed to complete the construction, I thought I'd post about it here.
I needed to get a Lexan overlay for my CP that is being built.  I wanted a thin overlay since my CP top is 3/4" plywood so I didn't want a big, thick overlay on top of it.  I wound up finding 
www.usplastic.com and was able to buy a 2 foot by 4 foot piece of 1/16" thick Lexan for only about $30 when shipping was included.  Since the sheet is so thin, it is very easy to work with and the test cuts I've made have been perfect.  I ordered it earlier this week and received it yesterday so it arrived VERY quickly.  (Much quicker than my latest order from Happ which has taken over 3 weeks now.   

).
So if you're looking for Polycarbonate or Acrylic sheets for your cabinet, check out usplastics.  I have been quite happy so far.
EDIT:  Perhaps we could make this thread a sticky so we'll have a constantly up to date place to buy Lexan and/or Plexiglass if needed.  I'll list all the sites below:
US PlasticsTAP PlasticsE-Street Plastics