I am looking for a set of plain icons ( 64 x 64 or 128 x 128 ) in an SVG, PNG or JPEG format that have a similar yet basic design for a personal project. The icons need to be for file types ( like jpg, pdf, doc, xml, rss, php etc ) and need to have some format to their filename that would allow a program to select the right icon for the right file extention.

Although I have tried to get my own collection going, it is hard to get them all to have a similar style and look. Does linux have any collections like this?

If anyone can help I would be greatly appreciative,
Thanks!