How to use Steam API and log in through steam on my website?

[Phunk]

Hey guys, I'm looking how to go about using steam to log into my forums. Though I am not very familiar in php, I am efficient in lua, and have taught myself everything over a year. I learn fast. Means of compensation can be discussed. Please contact me if you can lend a helping hand!
I plan to integrate this with mysql and paypal api to make an auto donation system to, so as a secondary matter, help with that would be great!

thanks guys, and live happy

[Didgy]

Lua will be of no help with your project I'm afraid.

Is this an existing project you are adapting or a new venture?
Is your form an off the shelf package? if so, which one?

The Steam API responses are either JSON, XML or VDF, so I'd suggest reading up on at least one of them (I'd go for JSON personally).

Details on the Steam API can be found here: http://steamcommunity.com/dev
You sign up for an Steam API key here: http://steamcommunity.com/dev/apikey
Terms of use are here: http://steamcommunity.com/dev/apiterms

To facilitate login through Steam, you will also need an OpenID library, there are some here: http://openid.net/developers/libraries/#php
However, if you are using an off the shelf forum system there may be an existing module/plugin/codebase you can use.

With regards to "Auto Donation", are you talking about a subscription service (i.e. fixed term recurring payments)?
If so, take a look here: https://developer.paypal.com/webapps/developer/docs/classic/paypal-payments-standard/integration-guide/subscribe_buttons/

Feel free to add me on Steam if you need any assistance.