Good for you and welcome to Crackberry!! :)
I love using my PB, which I do on a daily basis, including for reading my ebooks. (I don't like the flat e ink screen on my Sony 650)
Here are thread links to 2 excellent ebook readers which you can purchase from the Playbook App World:
Book Reader for EPUB and Kindle Books (AUD $1)
http://forums.crackberry.com/playboo...aybook-638953/
Pdf Reader (AUD $1)
http://forums.crackberry.com/playboo...reader-718636/
Have you set up your Blackberry ID?
I think you'll find many many uses for your new PB - and if you take a scroll through these threads and also the PB Apps thread you'll find some wonderful ideas on how to get the best out of it.
Enjoy!!! :D