Yes. Emailing them is also pretty good way to transfer textures.
Tho, there are other ways too.
You can pack the files to .zip/.rar folder and upload it to any file sharing website (e.g box.net, mediafire.com).
Or you can uload images to imagehosting site (e.g imgur.com, imageshack.com etc) and PM links to your buyer.
Last edited by firebolty; Feb 4, 2012 at 11:44 PM.
Reason: Edited typo in link to prevent future whining