Hi there,
Here's an entire website of documentation on the PhotoBucket API:
http://photobucket.com/developer/[
^]
Yes, well spotted, that is the PhotoBucket developers site! You should try searching for stuff like this. Most API's have documentation - as I learnt from writing my own C# Libraries for the Facebook, LinkedIn Twitter and PayPal API's - the documentation may not always be easy but most of the time, everything you need is there! Just search for it... You cannot expec us to give you an entire lesson on how to use the PhotoBucket API in one answer - they have a whole site for it!
Hope this helps,
Ed
(Also, you didn't say which PhotoBucketNET.dll - there could be many - you should cite your sources when posting in relation to a specific library/piece of code).
Edit: To aid the OP. Go to the site. Click "Read" under documentation. Do "View web format". It looks unhelpful inmitially - click on the Index tab in the bottom right corner of the web page - hey look! Everything you are looking for all nicely laid out with full details :) Whatever PhotoBucketNet library you are using will be structured and will function the way the documentation for the PhotoBucket API says it should.