If you're looking for a "bolt in" LCD touchscreen for your 08 Yaris, I think you're in for a looonngg search.
You might be able to find an adapter kit to fit one of the double din pre-packaged nav systems (ie: avic-d3, etc) but I highly doubt anyone offers one to fit a lilliput, xenarc, etc into a stock opening. That's why most people here end up custom molding their own in.
Or you could go with a motorized flip out screen. Most of them fit into a standard aftermarket radio adapter kit.
Cheers and Good luck.