I understand there are tweaks to change the Places Bar Object, however there are only certain ones for what I can see that you can changee.

From the example picture:

What I want to know is if I have certain folders used to back my files, sorted by types. for example Wallpapers/Adobe Pictures/Macromedia Websites.....

Can I create folders in the Places Bar to reflect these?

You can add custom locations to the places bar using TweakUi. You need to manually type in or copy and paste the location of the folder in the drop down boxes.

For example, if you wanted to add a folder called Downloads that resides in your My Documets folder, you would type the following in one of the drop down boxes - C:\My Documents\Downloads

-Clayton