How-to for creating icons

I know a lot of themes come with PSD's for creating icons, but I still don't really know how to do it. I have no experience with photoshop at all.

Is there a good, up to date guide someone can point me to? I started looking and found some, but realized the information was kind of old.

Is Photoshop really the only good option as far as the software to use? What version is sufficient? I can't spend hundreds of dollars to create icons.

Thanks for any help.

 

Sorry for the title. I've tried google, most of the info I've found seems to be a little old, but I'll keep reading. Thanks