A paper on interior design history?

You could start here:

http://en.wikipedia.org/wiki/Interior_design#History_of_the_interior_design_profession_in_the_US

Have you tried visiting a public library?

Barring that, you really need to be slightly more explicit regarding the target of your intended paper. How far back do you need to go? A hundred years back? Two hundred year's back? Do you need to write specifically on interior design history for the US, Europe, Asia, etc...?

Here's some reading material for you to get started with:

http://www.architectureweek.com/2001/0905/culture_1-1.html

http://www.metmuseum.org/toah/hd/ench/hd_ench.htm

http://venturist.hubpages.com/hub/Interior-Design-History

http://www.slideshare.net/kaash7827/history-of-interior-design-3

http://www.austinalchemy.com/pdf/JSAH2006.pdf

yeah but Exterior painting and or designing takes a lot of time and imagination but in order for you to have an example, you may have to Google it all the time.

If you are going to write a history of Interior Designing, you must go first to library and search the internet for possible ideas about internet designing. You must get only the important words and then later you're going to organize it and make a draft. Lastly, read it carefully for furnishing.

Little late for that now, wouldn't you say? That question was filed January 2012!!!