The first file share that I use a lot is from Microsoft. All of the photos are free-share, meaning that they do not have copyright issues. Lucky for me, there are hundreds of files on this file share; and lots of instrument pictures. At work, most of my posters are concert related. Therefore Instrument backgrounds are common.
http://office.microsoft.com/en-us/images/ - This is the address for the microsoft images - I recommend bookmarking it so that you can use it whenever you need it.
|This is an example of the results you get with a simple search. I used the word "instrument".|
This is a second site that I use, although it is not nearly as exhaustive as the Microsoft file share.... http://www.copyrightfreephotos.com/ The downside to this site is that it does not have the search function available with the other site, but there are good quality images.
http://www.freedigitalphotos.net/ This website has a very well organized selection of free photos, it also has a search function. The left-hand navigation menu has a list of categories (and sub-categories) of thousands of popular photos.
http://www.stockvault.net/ The stockvault website is more on the design-heavy side. It is a valuable resource for design conscious individuals, although it has less type-specific images.
http://freerangestock.com/index.php Free stock photos are also available from this site - and there are some very high quality stock photos on this site, and guess what? There is a search function!
Everything In Place Please