There are sometimes issues with using free web icons …
- restrictive license (several free icon sets require a credit or simply cannot be used on commercial sites)
- you want something more unique - because they are free you often see the free icon packs used - you might want something less commonly used
If free icons are not suitable because of the reasons above or if you can’t find what you are looking for among the free web icon resources here check out these cheap web icons from iStockphoto. I am a big fan of iStockphoto - not least because you get a good quality free stock image every week (there is no cost to join to get access to these). They have great search features and a huge selection of photos, icons and vector images.