So for the nitty-gritty (applies to Typepad).
Once you have selected some images you like,
save them onto your hard-drive and upload them into your files section in the Control Panel. Then decide which Typelist you'd like to add the image to and select the list. You can attach the image anywhere into your list or in the label section of a Typelist and this will attach it to the list title (see example in my right sidebar labeled "Sharing is Twice as Nice").
The code to insert is:
[img src =[a href="http://urlgoeshere/"]
(please change the square brackets to the pointy ones)
and if you want to make it as a link you would use this code:
[a href="linkURL"][img src="imageURL"][/a] .
This is a nice way to thank the site that is offering their lovely images for web users by attaching a link somewhere within your blog. To insert the image url into the code simply copy and paste the image url into the space within the code. (Remember to change to brackets to pointy ones).
I hope this is helpful to someone. Let me know if you have any questions, I know I've asked Lissa just about ALL of the questions there is about template tweaking, so I'm happy to help too if I can!
Have fun!! Blessings!