Custom image development

I need images for use on a website in support of articles being published online. I will need 20 images initially for this current project. There will be a monthly requirement of 8-10 images thereafter (through a different project). All images should be original and will be delivered to me in Adobe Photoshop/PSD format for alterations/enhancements if necessary. I will provide detailed description along with a pen sketch for each image. Images will be about a new process or product and may involve 3D views but no animation or complex artwork. Each image will likely use 5-8 basic shades and will be 800x600 pixel size.