Going through all of my online resources on Latvian has been slow-going. Some of them have been discontinued, moved or difficult to classify. This one is too good to hold back, however. I found it at PageF30, who has some great resources on learning languages too.
There is a very important poem/saga called Lāčplēsis, which is regarded as Latvia's national epic. It was written in the late 1800s by Andrejs Pumpurs and based on local legends and fairy tales about the hero Lāčplēsis, or, the Bear-slayer. (Read more about it at Wikipedia.)
You can now listen to the whole saga online for free and follow along with the text. The reading is really quite good. Unfortunately, the link for the full text is bad at LibriVox because AILab changed everything over to Korpuss.lv. (Both Korpuss and AILab are great Latvian resources, by the way.)