Data Entry: Upload Images to site through CMS

Hello Coders, I have a simple job for you all. I have approx 600 images of products which I need to upload to my ecommerce shop. I have already put in all the information about the products, but not all the images as this is a time consuming job. Some products have 4 images associated with them, some have less. It will take about 1 minute at most to do each product and there are approx 150 products. I estimate this job will take no more than 4 hours. You have to: 1) Log into admin section on website. 2) Click manage products 3) Select the first product which has no image. 4) Click 'image settings' for the product. 5) Find the relevant images from the ones I sent you (they are categorised properly). 6) Upload each image, click next, then update. 7) Repeat from step 3. Easy as that. Finally, I need this done quickly. You must be ready to start now and finish shortly after. Hopefully in the next 12 hours. Thanks.