PicTree theme

Hi I have been trying to change the photos under Portfolio for 6 months now but has no clue on how to do so.
Wordpress does not have a contact page and I am going crazy here. I need to change those pics soon since they were taken 2 years ago and are not up to date how I photograph now and I am surprised clients still contact me after seeing them..

Please help. How do I change the photos under PORTFOLIO

Thanks
Gunilla

http://www.sugarlightphotography.com

http://wordpress.org/extend/plugins/horizontal-scroll-image-slideshow/