At my shiny new community,
danny_jordan, we got a question on how to properly credit icons. I remember I had a hard time tracking that info down myself when I was new.
1. Avoid Hot-linking
You should not use the URL of the icon in the post to upload the user pic. Instead save it to your own computer/server.
2. Remember the Maker's Username
Anyway you can remember it is fine. My system is to save the image with the Username as the first part of the file name so I can have an icon archive that always tells me who to credit.
3. Credit When You Upload
When you upload a userpic, you have two places to enter text.
The "keyword" can be anything you want: something to remind you later what the icon is of. I think of it as a title.
The "Comments" is where you want to credit. You want to enter the username of the maker here, and you want it to be a link to their journal. To do this, you have to use a code. The final product looks like this:
houseketeer.
The code to enter follows. Replace USERNAME with the actual username of the maker.
This same code can be used anywhere on livejournal to make a link to a user or community.
4. Reading Credits
The above is all fine and dandy if you are snagging an icon from an icon post. But what if you fall in love with an icon you see someone using? How can you learn who made it so you can go ask that user permission to use it yourself?
You can view the userpics of any livejournal user, along with comments and keywords. If they are a good little Livejournal user, they have properly credited.
Just replace the username at the end of the URL with the username of interest. So here are my userpics, which are all credited:
http://www.livejournal.com/allpics.bml?user=houseketeer
It's that simple! Happy icon hunting.