Check out the PHP library called Guzzle. It's a nice wrapper for RESTful type APIs.

http://guzzlephp.org/

I wrote a wrapper for BTC-e REST API using Guzzle and Symfony framework. Even if you're not using Symfony, the client.xml service description can still be used with Guzzle to execute requests against BTC-e.

The BTC-e API actually has a few really annoying bugs and limitations (no market orders, missing the trade order ID if the order was executed immediately, etc....). I haven't made the code public on my GitHub yet because it's embedded with an app. PM if you'd like me to send you the source and I can share as well as explain the API bugs I encountered and how I worked around them. Hopefully this is helpful.