You can get all TSIBs, shop manuals as well as other references from the Lexus/Toyota Technical Information System.
http://www.techinfo.lexus.com/
It is not free though, subscription access to TIS is offered in daily, monthly, or yearly intervals following the rate schedule noted below.
Daily $10.00 US
Monthly $50.00 US
Yearly $350.00 US
So for $10.00 you can spend a few hours downloading all the TSIBs for you car. If you are really ambitious you can spend a whole day downloading your shop manual in small chunks. The information you get is worth far more than $10.00 and will pay itself off rather quickly.